When I first read through F. Piper's Christian Dogmatics, I was a Calvinist. By the time I had finished volume III, I was convinced that there was simply no exegetical foundation for many core Presbyterian beliefs, primarily in reference to the two natures of Christ and the sacraments. These volumes were one of the most important factors in my decision to join Lutheranism. I decided to reread them now as a convinced Lutheran. I am going to put up reviews of each of the three volumes, as I have no noticed several things I both agree and disagree with as a Confessional Lutheran within his Dogmatics.
Pieper spends a considerably large portion of the first volume on Prolegomena. The main point he gets across is that scripture itself is the sole authority of all theology. He argues against 19th century liberalism, which was prominent during his writing. Neither reason nor experience is above scripture. He sees both the reformed and Roman churches as flawed in similar ways. The Roman church places it's own tradition and magisterium above scripture. The reformed church, though they profess sola scriptura, too often make doctrinal formulations based upon logical deduction. For example; some men are saved and not others. Those that are saved are only converted by God's own choosing, therefore, those who are damned are only damned due to God's own choosing. When first reading this, it made me think about two books in particular which have been staples of Reformed theology for years: John Owen's the Death of Death, and Jonathan Edwards' the Freedom of the Will. Ultimately, much of Reformed theology, specifically the doctrine of limited atonement is not based upon clear exegesis but logical argumentation. When I was reading through Hodge's systematics (at the same time I read Pieper) I noticed that his whole argument against the Lutheran doctrine of the communication of attributes of Christ's divine to his human nature, was based on the fact that he had decided that to be human means to be present in one place at one time.
The next section in the book is on Holy Scripture. Here he defends the older orthodox theologians who had been attacked so often by 19th century liberalism. He spends much of his time defending the fact that Luther also taught Biblical inerrancy. Pieper discusses the Homoleugomena, Antileugomena distinction taught by the Lutheran fathers. This distinction comes Eusebius. The books of the New Testament are categorized by acceptance in the early church. Some books have been universally recognized: the 13 epistles of Paul, the four gospels, Acts, 1 John and 1 Peter. There was doubt in some areas about: 2, 3 John, Jude, James, Hebrews and Revelation. The first books listed are primary. All doctrine should be decided chiefly by books about which there is no doubt. The Antileugomena have been accepted as inspired by most in the Lutheran church (though there have been times when one has doubted one of these books), however they take a secondary place in establishing doctrine. I think that this distinction is valid, however, it seems that because God has led his church with these specific books for most of the 2000 years of church history, it would be acceptable to get rid of this distinction. It can be confusing and unhelpful.
The next section of volume I is on the doctrine of God. He begins this section by discussing the natural knowledge of God. He believes that man knows the existence of God a priori, through the conscience, and a posteriori, through creation. This knowledge however is never a saving knowledge which comes only through the gospel. Pieper then moves on to discuss the trinity. He defends the Nicene and Athanasian creeds. All who deny this are heretics. It is refreshing to read Pieper's blatant refusal to claim those who deny the trinity as Christians. In our day of relativism, barely anyone is willing to affirm that knowing even an essential truth like the Trinity is necessary for salvation. This is one of the highlights of the Dogmatics. Peiper's theology is thoroughly trinitarian. He defines concisely and clearly the false explanations of, and denials of the trinity which have arisen through out history and refutes them with scripture.
One thing which I found particularly interesting is the Pieper denies Augustine's explanation of the trinity. Augustine explains the trinity by describing the Father as love. The Father, as love, must have an object of love, thus the Son is eternally begotten as that object. The love itself between the two persons is the Holy Spirit. This always seemed too speculative to me, though I love Augustine. I agree with Pieper that this is not clearly taught in scripture. He also denies Melancthon's idea that God the father, when reflecting upon Himself creates in reality what he is reflecting upon. This is how the son is eternally begotten.
Pieper also has a very good section on the trinity in the Old Testament. He says, contrary to modern theology, that one can produce the doctrine of the trinity from the Old Testament, particularly in reference to the angel of the Lord and the Spirit at creation.