Reformation Day!

I thought that I would take this reformation day as an opportunity to write about the life of John Knox, the great Scottish Reformer who is firmly in our Presbyterian heritage.

First, I want to let everyone know that Ligonier Ministries is presently offering a free copy of the Reformation Study Bible for a donation of any amount. You can read about the offer here. I have a copy of this study Bible and while I'm not convinced that it was an improvement on the New Geneva Study Bible and it appears to have been surpassed in this translation by the new ESV Study Bible I think that most people will still find this to be a fantastic resource for personal study. Just make sure that you don't answer a "What does the text say?" question in Sunday School with, "The note in my Study Bible says..." :-)

The Life of John Knox

Iain Murray writes, “The most frequently user word in John Knox’s vocabulary was undoubtedly the word ‘battle’; and the battle, as he knew it, was ‘not against flesh and blood, but again principalities, against power, against the rulers of the darkness of this word (Eph. 6:12).” (8)*

Knox was born around 1514 in East Lothian. Not much is known of his early life but he did attend the University there and was ordained to the priesthood in 1536. From 1540 to 1543 he served as a church lawyer in East Lothian. At that time a new government allowed some toleration of Protestants and Knox was saved after hearing the preaching of Thomas Guylliame. When the Protestant preacher George Wishart came to East Lothian in the winter of 1545-6 Knox waited on him, which included guarding the preacher with a two-handed sword against assassins. Eventually the preacher ordered Knox to return to teaching and that night Wishart was seized and later burned at the stake by Cardinal Beaton outside St. Andrews.

After Beaton himself was later assassinated some pled with Knox to take up the pulpit at St. Andrews. He preached on the Gospel of John for a short time before the castle was attacked by French galleons and Knox, along with the 120 defenders, was taken as a prisoner to France. After this, Knox tells us in his autobiography that he spent nineteen months as a slave rower aboard a French galley. After English intervention Knox was released and spent time preaching in England before fleeing back to Europe after Mary Tudor took the throne. During this time he married Marjory Bowes but, having left her in the north for her safety, he was not able to get back to her before having to flee the islands.

Knox spent a number of years in exile from Britain at Geneva where he studied theology under the French Reformer, John Calvin, and pastored an English-speaking congregation in the city. After twelve years in exile he finally returned to Scotland in 1559. The Scottish Reformation became an armed conflict when the “Lords of the Congregation” and the Catholic lords raised armies and met in several battles. Knox served as the spiritual leader of the Protestants who preached and ministered to the soldiers and leaders as well as securing funding from English allies. When military aid finally came from England the Protestants prevailed and the Scots’ Confession (written by Knox) was ratified at the first Scots Parliament in 1560.

Mary Queen of Scots returned to the country in 1561 and Knox was in conflict with her and her supporters for the next six years until the Protestant forces again took up arms in 1568 and she was forced to flee back to England where she was eventually executed. At this time James VI of Scotland (later James 1 of England) became king though he was only an infant. A protestant Regent was appointed but after his assassination Knox was forced to leave Edinburgh and return to St. Andrews with his family.

Knox was not the human cannonball that he is often made out to be. Instead he was a well-cultured man who understood when Christian duty called for moderation. Iain Murray argues that his ministry can best be summed up as encouragement. Before his wife could leave England to join him in Geneva he wrote to her in a letter, “Your imperfection can have no power to damn you, for Christ’s perfection is reputed to be yours by faith, which you have in his blood.” (27) While in Geneva he wrote back to the believers suffering for persecution under Mary Tudor:

Be not moved from the sure foundation of your faith. For albeit Christ Jesus be absent from you (as he was from his disciples in that great storm) by his bodily presence, yet he is present by his mighty power and grace . . . and yet he is full of pity and compassion. . . . Stand with Christ Jesus in this day of his battle, which shall be short and the victory everlasting! For the Lord himself shall come in our defence with his might power; He shall give us the victory when the battle is most strong; and He shall turn out tears into everlasting joy.” (27)

Above all Knox believed that Christ was seated on the throne of heaven and was king over all earthly rulers and powers. He believed that Christ had a great design for Scotland and continued to believe it through the days of exile, persecution, and even the early death of his first wife.

At the end of his life, it is reported that Knox was so weak that he could no longer mount the steps the pulpit on his own but had to be helped up. At the beginning of his sermons he would lean heavily against the lector and his voice could barely be heard in the far parts of the sanctuary at St. Andrews. Yet by the time he finished he would nearly be hopping up and down in the pulpit and speaking the words of Christ loudly as in his youth. Later in 1572 he was too weak to preach at all and had difficulty breathing so he spent his waking hours hearing Scripture read to him (especially Isaiah 53, John 17, and Ephesians). Murray writes this about his final hours:

On Monday, 24 November 1572, he insisted on rising and dressing but within half an hour he had to be put back to bed. To the question of a friend, Had he any pain?, he replied: ‘It is no painful pain, but such a pain as shall soon, I trust, put an end to the battle.’ There was further intermittent conversation that day and a last reading of 1 Corinthians 15 at which he exclaimed, ‘Is that not a comfortable chapter?’ About eleven o’clock that evening he said, ‘Now it is come’, and, lifting up one hand, he passed through his final conflict in peace. (33)

* All quotations in this essay are taken from Iain H. Murray, A Scottish Christian Heritage (Edinburgh: Banner of Truth Trust, 2006).

Here are some other lesser known Reformers to read about:
"John Wyclif: Morning Star of the Reformation" by Ra McLaughlin
"William Tyndale: Covenant Theologian, Christian Martyr" by Jules Grisham (Part 2)
"Theodore Beza" by Henry Martin Baird

Creator, Redeemer, Consummator

I just finished reading Creator, Redeemer, Consummator: A Festschrift for Meredith G. Kline (edited by Howard Griffith and John R. Muether). I thought that I would put a quick response summary up like previous ones for The Hope Fulfilled (soon to be posted), Resurrection and Eschatology, and Justified in Christ. Overall I enjoyed this book. I thought on the whole it was about equal to the Festschrift for O. Palmer Robertson.

Meredith Kline was an outstanding Old Testament scholar who worked at Westminster Theological Seminary, Gordon-Conwell Theological Seminary, and Westminster Seminary California. He authored a number of books and was a well-respected exegete. This Festschrift was originally published back in 2000 but republished after Dr. Kline was called home to be with the Lord on April 14, 2007.

1. “Evangelicals and the Comparative Method” by Tremper Longman III – This article asks how Ancient Near Eastern (ANE) texts should be used to help understand the Biblical writings. Longman presents some principles for how we ought to use these texts to deepen our understanding of God’s word. I thought that this was a helpful article with some good insights.

2. “The Treaty Concept and the Covenant: Recent Findings” by F. Charles Fensham – Fensham surveys a number of different scholars and their work on ANE covenant treaty documents (especially Hittite treaty documents) and their contribution to how we understand divine covenants in Scripture. This is a helpful summary from an academic perspective but probably will only be interesting to biblical scholars. Those interested in this subject would probably be more helped by reading Kline’s The Structure of Biblical Authority and Kingdom Prologue, and Far as the Curse is Found by Michael Williams, and Christ of the Covenants by O. Palmer Robertson.

3. “The Covenant Household: A Study of the Destruction and Salvation of Households in the Bible and the Ancient Near East” by Jeffrey Niehaus – This was one of my favorite essays in the book. Niehaus begins by surveying ANE materials to demonstrate that entire households were destroyed or saved based on the actions of the head of house. He then turns to Scripture to show that similar principles are used under the covenant. Niehaus closes by showing how the New Testament writers reveal that Jesus comes to rob the household of Satan and to establish his own household of God. A very interesting article.

4. “Kingship and Covenant in 1 and 2 Samuel” by J. Robert Vannoy – Vannoy surveys a number of Old Testament scholars who ask whether or not a king was part of God’s plan for Israel or if it was only an accommodation to the elders when they came to Samuel with a sinful desire to put a king over them in 1 Samuel 8. Vannoy then demonstrates the biblical evidence that a king was part of the plan of God for his people. This topic has been well addressed by conservative scholars and I don’t think that Vannoy adds anything new to the discussion but does sufficiently address the question for those unfamiliar with the subject.

5. “The Psalms as Response to God’s Covenant Love: Theological Observations” by Elmer B. Smick – Smick makes the case that the Psalms are supposed to be an “Amen” to the covenant ratification of Yahweh. To do this he discusses the Psalms in light of a number of theological categories. This is an excellent essay surveying the Psalms to show how this part of the wisdom literature fits the covenant nature of all of Scripture.

6. “Intrabiblical Exegesis and the Effusion of the Spirit in Joel” by Raymond B. Dillard – Dillard examines Joel 2:28-32 where the pouring out of the Spirit is promised in light of its context in Joel, in the rest of Old Testament literature, and in light of the New Testament use of the passage. I really enjoyed this article and thought that it was a very helpful treatment of the subject.

7. “Old Testament Gospel as Prologue to New Testament Gospel” by Royce Gordon Gruenler – Gruenler builds on a suggestion by Dr. Kline that the Old Testament redemption narratives, particularly the Exodus, form a type of the New Testament gospel of Jesus Christ. He examines this by looking at the Gospel of Mark to show that it answers and builds on the Old Testament redemption narratives. A good essay and probably a very good example of the average quality of the works in this anthology.

8. “Baptism, Servanthood, and Sonship” by Allen Mawhinney – One of Kline’s best known works is his The Oath Consigned where he examines Christian baptism in Old Testament context as a water ordeal undergone by Christ. Kline focuses mainly on the judgment aspect of baptism in this work. Mawhinney works within the context of Kline’s insights to examine the blessing and adoption aspect of baptism. This is a helpful essay though it would be good to have familiarity with longer discussions on baptism such as Murray and Strawbridge as a background.

9. “The Structure and Plan of John’s Apocalypse” by G.K. Beale – What I liked best about this essay was how it really helped to emphasize the literary depth of John’s work in this book. That said, Beale’s essays are generally very long and packed with material and this is no exception. It takes a while to get through this essay though it is worth the effort.

10. “Calvin on the Four Last Books of Moses” by W. Robert Godfrey – This essay is a summary and review of Calvin’s commentary on the harmony of Exodus, Leviticus, Numbers, and Deuteronomy. Godfrey’s essay reads very easily and is a good summary of Calvin’s work on these books. Readers unfamiliar with Calvin’s commentaries will get an excellent introduction to them here.

11. “Herman Bavinck on the Covenant of Works” trans. by Richard B. Gaffin Jr. – This essay is Dr. Gaffin’s translation of several chapters in Bavinck’s Reformed Dogmatics dealing with the covenants of works and grace. Bavinck is as eloquent and helpful as ever here. When this work was added to the Festschrift Reformed Dogmatics had not yet been translated into English as a complete work.

12. “What is Biblical Theology? Reflections on the Inaugural Address of Geerhardus Vos” by James T. Dennison Jr. – Dennison summarizes the thoughts of Geerhardus Vos on the nature of Biblical Theology and its relationship to other theological disciplines. This is a helpful summary but shouldn’t be anything new to those who have read Vos, Warfield, Murray, Gaffin, and Poythress.

13. “Covenant, Universal Call, and Definite Atonement” by Roger R. Nicole – This is a typically excellent essay by Roger Nicole. Those unfamiliar with his work should read the anthology of his works. Nicole presents an explanation and defense of the Reformed doctrine of Definite Atonement. This is a very readable and helpful article.

14. “Image of the Spirit and Image of God” by Paul Helm – Helm offers a response and review of Dr. Kline’s work, Images of the Spirit. I think that helm is overly critical at times but on the whole this is a helpful survey of how theologians understand the image of God in man.

15. “Pierre Marcel on ‘Brothers and Sisters in Christ’” trans. by Howard Griffith – I’ve never read anything by Marcel before but I thought that this was a helpful study on what it means to be a part of the family of Christ.

16. “Reformed Theology as the Theology of the Covenants: The Contributions of Meredith G. Kline to Reformed Systematics” by Mark W. Karlberg – To me this essay was very similar to the essay by Helm. Both were examining a part or several parts of Kline’s work in terms of its value to systematic theology. Ironically where I found Helm to be somewhat overly critical it seems like Karlberg is overly apologetic in Kline’s favor. The two essays partially help to give balance in thinking about Kline’s contributions.

17. “Redefining Merit: An Examination of Medieval Presuppositions in Covenant Theology” by Lee Irons – Irons addresses the question that has come up often recently in the context of the Federal Vision debate of where grace fits in the covenant of works. I had a very mixed reaction to this essay. It was very helpful in addressing the subject and pushing the discussion forward. At the same time there also seemed to be some holes in Irons’ conclusions. On the whole this was useful though not great.

18. “Van Til and Theonomic Ethics” by T. David Gordon – Gordon examines and evaluates the claims of theonomists that their ethics were shared by Cornelius Van Til. This is interesting in light of the debate between Kline and Bahnsen over the application of Old Testament law for modern governments. Gordon is very helpful in showing the differences between Van Til in Christian Theistic Ethics and Bahnsen while acknowledging that there are some similar convictions especially in their starting points.

19. “Cult and Culture” by William Edgar – This was a great essay to finish the book with and one of my favorites. Edgar examines how the work of Kline, especially in his Kingdom Prologue, helps us to build a biblical theology of culture. There are a number of helpful conclusions and thoughts in this essay.

Sunday School Reading for October 26, 2008

Here are some reading recommendations from our discussion of the doctrine of man last week. There are not many book recommendations on here simply because there are not a lot of books that focus particularly on the doctrine of man. Instead I mainly have articles that you can read online for free recommended and then relevant sections in systematic theologies.

First, this week covered a number of questions from the Shorter Catechism:

Q12. What special act of providence did God exercise toward man in the estate wherein he was created?
A12. When God had created man, he entered into a covenant of life with him, upon condition of perfect obedience; forbidding him to eat of the tree of the knowledge of good and evil, upon pain of death.

Q13. Did our first parents continue in the estate wherein they were created?
A13. Our first parents, being left to the freedom of their own will, fell from the estate wherein they were created, by sinning against God.

Q14. What is sin?
A14. Sin is any want of conformity unto, or transgression of, the law of God.

Q15. What was the sin whereby our first parents fell from the estate wherein they were created?
A15. The sin whereby our first parents fell from the estate wherein they were created, was their eating the forbidden fruit.

Q16. Did all mankind fall in Adam's first transgression?
A16. The covenant being made with Adam, not only for himself, but for his posterity; all mankind, descending from him by ordinary generation, sinned in him, and fell with him, in his first transgression.

Q17. Into what estate did the fall bring mankind?
A17. The fall brought mankind into an estate of sin and misery.

Q18. Wherein consists the sinfulness of that estate whereinto man fell?
A18. The sinfulness of that estate whereinto man fell, consists of the guilt of Adam's first sin, the want of original righteousness, and the corruption of his whole nature, which is commonly called original sin; together with all actual transgressions which proceed from it.

Q19. What is the misery of that estate whereinto man fell?
A19. All mankind by their fall lost communion with God, are under his wrath and curse, and so made liable to all the miseries of this life, to death itself, and to the pains of hell forever.

One thing that we did not take time to discuss in class because of limited time is the image of God in mankind. Just to give you some recommendations this is covered by Anthony Hoekema in Created in God's Image and by Meredith Kline in Images of the Spirit. Hoekema's book is far easier to read and written from a systematic perspective to examine what it means to be created in the image of God before and after the fall and then as restored humanity. Kline's work is more biblical theological. I do have some concerns with some of Kline's conclusions, and so I would recommend the Hoekema book more highly, but on the whole I think that this is a very good book from a fantastic exegete and biblical scholar.

The other book that I would recommend is John Murray's The Imputation of Adam's Sin. I should warn you that this is a typical work of Murray in that it is written with a very high prose and on a high academic and scholarly level. That said, if you take the time to read it carefully two or three times then I think that it will be very rewarding. It is available as a standalone and also in the book Justified in Christ edited by Scott Oliphint, which I briefly reviewed.

Second, total depravity is dealt with in Chapter 3 ("Rebels without a cause") of Putting Amazing Back Into Grace: Embracing the Heart of the Gospel by Michael Horton and Chapter 2 of What's so Great about the Doctrines of Grace by Richard Philips.

Next, John Calvin deals with the doctrine of man in Book 1, Chapter 15 and sin in Book 2, Chapters 1-3 of his Institutes of the Christian Religion. Herman Bavinck discusses the doctrine of man in Volume 2 (God and Creation), Part 5, Chapters 11-13 and sin in Volume 3 (Sin and Salvation in Christ), Part 1, Chapters 1-4 of his Reformed Dogmatics. Charles Hodge addresses man in Volume 2, Chapters 1-5 of his Systematic Theology, the covenant of works and the fall in Chapters 6-7, and sin in Chapters 8-9. A.A. Hodge covers man in Chapter 14 of his Outlines of Theology, the covenant of works in Chapter 15, and sin in Chapters 16-18.

Finally, here are some articles and books that you can read online for free dealing with these topics:
Thomas Boston: "Man's Utter Inability to Rescue Himself"
John Murray: "The Adamic Administration" (Note: Professor Murray objected to calling the pre-fall relationship between Adam and God a "covenant" but he did believe everything that we would say is contained in the covenant of works)
A.W. Pink: "The Doctrine of Man's Impotence"
A.W. Pink: "The Total Depravity of Man"
Charles Spurgeon: "Human Inability"
B.B. Warfield: "The Plan of Salvation"
James Henley Thornwell: "Is there Good in Humanity Apart from God's Grace?"
Robert Lewis Dabney: "Adam's Fall and Free Will" (Note: part of the reason that I recommend these articles by Thornwell and Dabney is that these are two very gifted theologians who are part of our history as the Southern Presbyterian church. Both were certainly in err and sin when it came to their views on slavery but they were still blessed by God with great minds and understanding of his word and so it does behoove us to study their works)
This page has a list of references that teach total depravity.

As a post script, I would recommend that people take the time to read and consider the third and fourth heads of doctrine from the Canons of Dort. These two heads deal with the doctrines of total depravity and irresistible grace. As a church that traces its history through the Scottish Presbyterians we in the PCA do not subscribe to the Canons of Dort but only to the Westminster Standards. That said, churches that come from continental European roots subscribe to Dort as one of the three forms of unity (along with the Belgic Confession and the Heidelberg Catechism) instead of the Westminster Standards. While I do prefer Westminster as a whole I think that we can learn much by seeing how others have tried to systematize the teachings of Scripture for the church to confess and as Dort was a response to the Arminians I think it quite helpful in studying the doctrines of grace.

Sunday School Reading for October 12, 2008

Sorry that it took an extra day to put this up this week but here are some recommended reading on the decree of God and unconditional election. There are a number of articles that you can read online free regarding this topic and it will be addressed in any good Presbyterian or Reformed systematic theology. First, here are the related catechism questions and answers:

Q7. What are the decrees of God?
A7. The decrees of God are his eternal purpose, according to the counsel of his will, whereby, for his own glory, he hath foreordained whatsoever comes to pass.

Q8. How doth God execute his decrees?
A8. God executeth his decrees in the works of creation and providence.

Q9. What is the work of creation?
A9. The work of creation is, God's making all things of nothing, by the word of his power, in the space of six days, and all very good.

Q11. What are God's works of providence?
A11. God's works of providence are his most holy, wise, and powerful preserving and governing of all his creatures and all their actions.

Again, I'll repeat the recommendation of John Frame's The Doctrine of God. Professor Frame more than adequately covers all of the topics that we talked about under the doctrine of God including the decree.

Regarding the doctrines of grace, since unconditional election is the first of the letters from the TULIP acronym that we've addressed, I'm just going to recommend two books that cover this topic and everytime we discuss one of the doctrines of grace I'll note the relevant chapter. This is mainly because there are a large number of introductions to presbyterian/reformed/calvinist theology that cover the doctrines of grace. Many of them are pretty good. These are the best two that I've read in terms of being complete, orthodox, and applicable and so rather than advise people to buy an even larger number of books I think that these two (particularly the Horton book) will be more than sufficient though I'd be happy to recommend more if people ask.

Putting Amazing Back Into Grace: Embracing the Heart of the Gospel by Michael Horton - Dr. Horton is probably best known as the host of the Christian Radio program, the Whitehorse Inn. He is professor of theology and apologetics at Westminster Seminary California and the author of a number of books addressed to various audiences. This book is concentrated on introducing readers to the basics of the Reformed faith (and I recommend it above the following book simply because it covers more than just the doctrines of grace). Dr. Horton discusses the subject of unconditional election in chapter four, "Grace before time."

What's So Great About the Doctrines of Grace? by Richard Philips - Reverend Philips is the senior pastor of Second Presbyterian Church in Greenville, SC. He has a pastor's heart and a seminarian's mind. I like this book about the doctrines of grace because Pastor Philips is focused on developing the doctrines through faithful exposition of Scripture, on explaining why these doctrines should lead the believer to worship our sovereign God, and finally on showing how these doctrines are important for the Christian life. Pastor Philips deals with unconditional election in chapter three.

Second, here is a quick survey of where the decrees of God are discussed in Reformed systematic theologies. John Calvin principally deals with the decrees of God in Book 1, Chapters 16-18 of his Institutes of the Christian Religion and then election in Chapters 4-6 of Book 2 and 21-24 of Book 3. Herman Bavink addresses the decrees and election in Chapter 7 of the second volume of his Reformed Dogmatics (God and Creation) and then God's providence in Chapter 4 of the same volume. Charles Hodge discusses the decrees and providence of God in chapters 9 and 11 respectively of his Systematic Theology (available free here as a .pdf file). A.A. Hodge deals with these doctrines in Chapters 9, 10, and 13 of his Outlines of Theology (available free at Google books and for sale at the Shady Grove bookstore).

Finally, here are some articles that you can read for free online:
"On the Predestination of the Saints" by Augustine - Helpful to see that the doctrine did not originate in the 16th century.
"Predestination and Free Agency" by W.E. Best
The Reformed Doctrine of Predestination by Lorraine Boettner
"Of Election to Everlasting Life" by Thomas Boston - A sermon by an old Scottish Puritan Presbyterian.
"Electing Love" by Robert Murray M'Cheyne - A sermon on John 15:16 by a gifted Scottish Presbyterian minister (see a post on Pastor M'Cheyne further down in the blog or Andrew Bonar's biography of his life available at the Shady Grove Bookstore).
"Calvin, Dordt, and Westminster on Predestination: A Comparative Study" by John Murray
"The Sovereignty of God" by John Murray
"The Doctrine of Election" by A.W. Pink
"Election" by Benjamin B. Warfield

Some things from around the web

Here are a few things that I found today.

First, here is an article by Justin Taylor on the ESV Study Bible. It includes several pictures of Herod's Temple. Enjoy!

I've avoided putting anything political up here but this is a very good post from Nicholas Batzig (a PCA pastor in Pennsylvania) on the government and charity. Hopefully I'll have time one day to put up a summary my views of a Biblical economic.

Here is a link to the latest edition of the New Horizons magazine (an official publication of the Orthodox Presbyterian Church). The subject of this issue is the Dutch theologian Herman Bavinck. I haven't read everything by any stretch but as far as what Systematic Theology work I have read I consider his Reformed Dogmatics to be second only to John Calvin's Institutes of the Christian Religion. Since we are in the PCA, here is the latest issue of Equip to Disciple as well.

Finally, here is a quote from Michael Horton's new book, People and Place: A Covenant Ecclesiology (this is the fourth is a series of four on a covenantal systematic theology). This is a very good quote on Christ's real absence and his presence in the Spirit that is worth thinking about and meditating on (HT: Shane Lems):

The more we receive from the Spirit of the realities of the age to come, the more restless we become. Yet it is a restlessness born not of fear but of having already received a foretaste of the future. Only when we have caught the scent of everlasting life and joy that pervades the atmosphere of the consummation does the air of this present age seem stale and redolent of death. Having tasted the morsels of the heavenly feast, we no longer find the rich banquets of this age satisfying.

The Spirit’s presence always tantalizes us with the more still to be enjoyed, which makes Christian suffering different from either a nihilistic and cynical fate to be accepted with Stoic indifference or a reality to be denied in a spirit of triumphalism. Those who are filled with the Spirit are characterized by struggle more than victory, since it is the Spirit’s presence that draws the two ages into conflict and draws out the insurgents of this present evil age to defend their new contested terrain. Where the Spirit indwells, there is peace with God and conflict within, with the powers of sin and death within us and in the world. (pg. 23)

Sunday School Reading - October 5, 2008

Here is some recommended additional reading from yesterday's discussion. We didn't quite finish up the doctrine of God so most of the recommendations from last week will stay the same (as always, you can click the "Sunday School Reading" label at the bottom of this to see all related posts). So this week I will mention again one book, make a few recommendations that are focused on the Trinity, and then try to give you a few free papers to read online (in particular, I highly recommend taking the time to read B.B. Warfield's "The Biblical Doctrine of the Trinity").

First, here are our catechism questions on the doctrine of God:
Q4. What is God?
A4. God is a Spirit, infinite, eternal, and unchangeable, in his being, wisdom, power, holiness, justice, goodness, and truth.

Q5. Are there more gods than one?
A5. There is but one only, the living and true God.

Q6. How many persons are there in the Godhead?
A6. There are three persons in the Godhead: the Father, the Son, and the Holy Ghost; and these three are one God, the same in substance, equal in power and glory.

The Doctrine of God by John Frame - I just want to reiterate this particular book in terms of our whole discussion of the doctrine of God. While this is a very long book it is very rewarding and more than worth the time to read. Professor Frame addresses all of the areas that we are going over in our discussion and also deals with some other related doctrines. At least one or two copies of this book are available in the church library. His discussion of the doctrine of the Trinity is particularly good.

Father, Son, and Spirit: The Trinity and John's Gospel by Andreas Kostenberger and Scott Swain - This is a new book and is rather unique in its goal. It comes from a series on Biblical Theology. Yet because of the topic this book is a very good blend of Biblical and Systematic Theology. Dr. Kosternberger is a New Testament Professor at Southern Baptist Theological Seminary. Dr. Swain is a Systematic Theology Professor at Reformed Theological Seminary in Orlando. I just finished this book today and they bring together their respective areas of expertise to present a book that gives a faithful exposition of what the Spirit says about the Trinity through John and also examines it in light of the church's whole doctrine of the Trinity. I will warn you that this is a book written on a high academic level and Drs. Kostenberger and Swain interact with other scholarly works so it is not the easiest read out there. Yet both are skilled writers and I think that most people in the church should be able to read this book in a few evenings and glean a lot from it.

Keeping in mind our major works on Systematic Theology, the Trinity is not often addressed formally in Calvin's Institutes but instead Calvin wrote the entire work from a Trinitarian perspective (though he does deal with this doctrine in particular in Chapter 13 of Book 1). Book 1 focuses on God the Father. Book 2 focuses on both God the Father and the person of God the Son. Book 3 focuses on the work of God the Son. Book 4 focuses on God the Spirit. Herman Bavinck's Reformed Dogmatics is similar in outline though chapter 6 of the second volume focuses on the Trinity in particular. Charles Hodge addresses the doctrine of the Trinity in chapter 6 of volume one of his Systematic Theology (available online as a .pdf file). A.A. Hodge explains this doctrine in chapter 8 of his Outlines of Theology (available for free on Google books).

Finally, here are some papers that you can read online on the doctrine of the Trinity:
Lorraine Boettner - "The Trinity"
Benjamin B. Warfield - "The Biblical Doctrine of the Trinity"
Benjamin B. Warfield - "Calvin's Doctrine of the Trinity"
James I. Packer - "Trinity"
John Owen - "A Brief Declaration and Vindication of the Doctrine of the Trinity" (warning: this is a .pdf file and no matter what the title nothing by John Owen is ever truly brief; this is 77 pages)
R. Scott Clark - "The Splendor of the Three-in-One God: The Necessity and Mystery of the Trinity"

Reformed Expository Commentaries

Normally I do not recommend whole commentary series anymore. There are so many different series (and single volumes) out there that its become more cost effective to just try to get the best commentaries for each book. I will make an exception here and put in a plug for the Reformed Expository Commentary series edited by Richard Philips and Philip Graham Ryken with Iain Duguid serving as Old Testament Editor and Daniel Doriani serving as the New Testament editor. All four men are pastors or former pastors who also have experience teaching at the seminary level. This gives the series a very helpful balance between practical application and scholarly treatment of the biblical material. Sinclair Ferguson says, "Here is exposition modeled by pastors with scholarly gifts and by scholars with pastors' hearts."

The series is still being published (I believe that the next release is a two volume work on Matthew's Gospel) so there are only a few volumes presently available. Currently available are Esther and Ruth (Duguid), Daniel (Duguid), Zechariah (Philips), The Incarnation in the Gospels (Doriani, Ryken, Philips), Galatians (Ryken), 1 Timothy (Ryken), Hebrews (Philips), and James (Doriani). Personally I have found Dr. Duguid's work on Daniel to be the best commentary out there on the book and Ryken's volume of 1 Timothy to be very valuable as well.

The reason that I bring this up now is because WTS Books has a special going on all eight volumes presently available. The list price for these books is $203.62. For now you can buy all eight for $112.16 (plus only $4 for shipping and handling). If you're looking for some accessible commentaries to use for either personal or family devotions then I highly recommend looking at these books.