Continuing my weekly series reviewing Grudem's Systematic Theology: http://cafetutorials.blogspot.com/2012/07/christian-theology.html
This week is chapter 7, "The Sufficiency of Scripture."
Grudem defines the sufficiency of Scripture as follows: "The sufficiency of Scripture means that Scripture contained all the words of God he intended his people to have at each stage of redemptive history, and that it now contains all the words of God we need for salvation, for trusting him perfectly, and for obeying him perfectly" (127).
The sufficiency of Scripture for Grudem means that we focus our search for God's words to us on the Bible alone (128) and have confidence that "we will be able to find what God requires us to think or do" on all our doctrinal or moral questions (129). This sufficiency is now complete, although it unfolded in stages. So at the time of the death of Moses, Grudem believes the first five books of the Bible were sufficient for God's people at that time (130). No further central redemptive acts have occurred since the death, resurrection, and ascension of Christ (and the unpacking of these events in the New Testament).
Grudem gives several practical applications that come from the sufficiency of Scripture:
1. We should be encouraged that everything God wants to tell us to think or do about an issue is found in Scripture (131). It may not always speak directly to our questions, of course, but it will at least do so indirectly if it is a matter of concern to God.
2. We are to add nothing to Scripture and to consider no other writings of equal value to Scripture.
3. "God does not require us to believe anything about himself or his redemptive work that is not found in Scripture" (132).
4. "No modern revelations from God are to be placed on a level equal to Scripture in authority" (132).
5. "Nothing is sin that is not forbidden by Scripture either explicitly or by implication."
6. "Nothing is required of us by God that is not commanded in Scripture either explicitly or by implication" (133).
7. "We should emphasize what Scripture emphasizes and be content with what God has told us in Scripture" (134). There are many topics that receive "relatively little direct emphasis in Scripture" (135), and while the Bible may have things to say about many of these things, these are not the areas that Christians should be focusing on.
The idea of the sufficiency of the Scriptures--like the clarity of Scripture--flows directly out of the Reformation and Martin Luther's debates with the Roman Catholic Church (RCC). Luther believed rightly that the Roman Catholic Church had added a number of doctrines and practices that are not clearly taught in the Bible. The Protestant dictum of "sola scriptura," "Scripture only," was thus a battle cry meant to peel back these accretions, things like purgatory and requiring priests to be celibate.
The place of my own tradition--the Wesleyan tradition--in relation to sola scriptura is a little ambiguous. Perhaps prima scriptura, "Scripture first," would be a little more accurate description of the practice of John Wesley, the father of Methodism. He is often said to have operated more in terms of a "quadrilateral" consisting of Scripture, tradition, reason, and experience, with Scripture primary. Nevertheless, the sufficiency of Scripture is taught in the Thirty-Nine Articles of the Anglican tradition from which Methodist churches like mine emerged, and the sufficiency of Scripture is in the Articles of Religion of my own Wesleyan denomination. (They are also implied by the Westminster Confession of the Reformed and in Cornelius Van Til's four characteristics that Grudem is building on)
Do I believe that the Scriptures are sufficient? Absolutely I do, and especially in two ways. Let me start with the easy one. The Scriptures are entirely sufficient for any matter of ethics because all of God's expectations are summed up in "Love God and love neighbor," where love of God means that one is completely surrendered to his will as you know it, and love of neighbor includes living lovingly toward one's enemies. The rest is working out the specifics.
The specifics are where Grudem and I no doubt will get into some disagreements, because it seems inevitable to me that many of the specific commands of Scripture were contextual and situational. Nor do I think it will be always easy to hone in on specific answers to ethical questions. In a complex world, love of neighbor can be a complex matter to work out and the Bible may or may not give much help. What is that verse about stem cell research again? I strongly suspect that Grudem's idea of finding answers in Scripture will often turn out to be just plain bad interpretation.
Secondly, I believe that Scripture contains "all things necessary to salvation," as the Thirty-Nine articles read. I would distinguish what God requires of us for salvation from the truths about how salvation works, with God judging us according to our (God-empowered) response to the light we have. But the fundamentals of how salvation works are even then quite sufficiently laid out in Scripture: God's loving grace, Christ's death, and my faith, all clearly there in Scripture.
But the Protestant sense of sufficiency goes well beyond what I just said. For example, the sense that the Thirty-Nine articles have is that "whatever is not read therein, nor may be proved thereby, is not to be required of any man or woman that it should be believed as an article of faith, or be thought requisite or necessary to salvation." So if the Bible doesn't require celibacy--or complete abstinence from alcohol--then no denomination should either. Groups that forbid having organs in worship because the Bible doesn't mention organs are ruled out of bounds.
As common-sensical as this sounds, the matter may be a little more complicated when we get into the details. Where, for example, does the Bible prohibit polygamy? Don't go for "the two shall become one flesh," because Jacob became one flesh with two wives and two concubines. The Old Testament freely allows polygamy (check out the rule in Deuteronomy 21:15-17), and the New Testament never explicitly prohibits it. I think it assumes monogamy in 1 Corinthians 7, but never commands it. No doubt Grudem thinks he can prove it from Scripture but, then again, he practices strange magic.
Similarly, it was about 400 years before most Christians believed in the Trinity in its current form. The main competition, Arianism, believed Jesus was the first of God's creation, the most exalted of all beings, but not "of the same substance" as God the Father. The key is that Arians made their arguments from Scripture just like their (winning) opponents did. Sure, we can read a statement like "I and the Father are one" (John 10:30) and fill it with our Trinitarian assumptions. I think God is fine with us reading it that way now. But it is not at all clear that John was saying anything related to the Trinity originally.
Although I don't want to get into the weeds, I would claim that when the Protestant Reformers (and when Grudem) speaks of the sufficiency of Scripture in matters doctrinal, they really mean the sufficiency of Scriptures as interpreted once the Trinitarian and Christological controversies of the first five centuries were over. Basically, the Scriptures are sufficient for Christian doctrine if they are interpreted the way they were once the theology of common Christendom was established. But one at least might argue that the Reformers did not actually peel back doctrine all the way to the New Testament church but back to the interpretations of the Bible that became dominant by around the year 451 at the Council of Chalcedon, when the Nicene Creed was finalized.