How might a doctrine of Holy Scripture be best articulated? Most evangelicals would point to 2 Timothy 3:16 as the place to start. For reasons I'll get to later, I'm not sure if that is truly the best place for such a foundation. Ultimately, our doctrine of Scripture must flow from from trust in a faithful God who wants to lead His people into truth, rather than a particular proof-text.
To start with the obvious, the Bible is a book containing words that its authors believed to be true. It is made up of books chosen by Jews and Christians because they believed them to be true and valuable for teaching. But the question arises: how do we know these words are true? How can we trust the authors when they are men like us, error-filled (Psalm 19:12) and culturally conditioned? What gives these words their authority?
There is One whose words are said to be true - YHWH, the Lord God. His words are pure (Psalm 12:6), perfect (Psalm 19:7-10), true (Isaiah 45:19) and truth (Psalm 119:160). If anyone can give us the Truth above the morass of human opinions, beliefs and confusion (Job 28:13-23), this all-knowing God can. What's more, it's reported that He wants to lead sinners into truth and to instruct people in what is right (Psalm 25; 31:3; 73:24), and that He is the shepherd of His people who wants to guide them (Psalm 23; 31:3: Ezekiel 34). These intentions are seen in how He reveals Himself through His words to His people through the prophets and fully in the person of Christ, as well as in his hatred for those who lead his people astray in matters of truth (Jeremiah 23). Indeed, throughout the Bible God speaks to various people so that they may
hear the truth. He is also portrayed as being able to
bring about whatever He desires, saying that His word accomplishes exactly what He wants it to do (Isaiah 55).
If this is the case, it's entirely possible that He has guided the authors of Scripture to write words that are flawlessly true, that we can trust - His words. He could even use words not directly quoted as being from Him, or even not originally directly inspired by Him, using them to teach us by placing them in the same canon as directly quoted words. By leading his people to accept those words as true alongside his quoted words - I'm thinking of narrative portions and books such as Esther, Ecclesiastes, and Song of Songs - He gives them as His own words, what He wanted to communicate to his people then and to his people now. It's therefore possible that He has guided His people in recognizing which books are from Him at all, leading to their canonization and contextualization through being part of the whole. This is not too difficult for the One who is able to do whatever he wants (Job 29:11; Psalm 135:6; Isaiah 55). If we trust that He, as our good Shepherd, has done this, we can have a truly firm foundation to build our beliefs on.
This seems to be the logic that Jesus and the early church used. They didn't have 2 Timothy 3:16, and yet they still affirmed that God had spoken Scripture not directly attributed to Him (Matt 19:4-5) and even spoken to Him (Acts 1:15-20), all the while relying on Scripture as being completely true.
Such a belief is unprovable, of course. But without it, it becomes quite impossible for our beliefs to have a possible basis in truth. With no clear guidance and revelation from a being who does know all things, we are left with our own guesswork, having no standard against which to judge the truth of our theology or ethics or hopes. If we don't believe that God has guided the authors and selectors of Scripture into all truth concerning those things, then we have no real basis on how to decide which bits of the Bible to believe and which not to. We end up choosing the bits we like and rejecting the bits we don't - but how on earth can we tell that we've made the right decision, or that God has spoken at all? Trust in God's desire and ability to reveal perfect truth to us, then, becomes essential, however that truth might be conveyed. Any other belief betrays a lack of trust in God's desire and ability to guide us, making society's zeitgeist or one's own standards the arbiter of what is true.
This means that 2 Timothy 3:16, 'All Scripture is God-breathed', is not the be all and end all of a doctrine of Scripture, and for good reason. There's an ambiguity in translating the verse: some translators would render v.16 as 'All God-breathed Scripture is also useful for teaching', taking the Greek kai to mean 'also' instead of 'and'. Others would say that the usual translation is much more likely (for instance, those behind the NET Bible), but are we just to place our faith in a stronger probability? Also at issue is the meaning of 'God-breathed'. Some would suggest it means 'breathed into' in the sense of Genesis 2:7, meaning that Scripture potentially contains theological and ethical error from men (just as Adam made mistakes), and God uses it merely as a pedagogical tool with many examples of 'what not to believe'. But there's another example of God breathing in Scripture: His breath directly created the host of heaven according to Psalm 33. This is besides the fact that it's natural to associate breath with words and that the text doesn't say God breathed 'into' Scripture as He did with Adam.
But if we trust that God wants to lead men into the 'knowledge of the truth' (2 Tim 3:7), then we must trust that He has given us the only words that could possibly be definitely true - His own. This informs our understanding of 'God-breathed', and also means that the syntax of the verse is not a make-or-break problem. Because we already trust that God has given us His words through man's words in Scripture, we know what those 'God-breathed Scriptures' are, however the sentence is translated.
What we believe Scripture to be, then, is informed by our trust in a faithful God who wants to communicate truth (John 16:13), rather than any trust in the probable meaning of a single verse. Of course, exactly what kind of flawless truth God wants to convey through the various texts of the Bible is a matter for discussion (as I've explored here, here and here) and we must be open to how He may have placed originally contentious sources together in this new canonical context to clarify, rather than contradict, each other. but for those who trust that God wants to guide us into the truth, a belief that He has breathed the entirety of the Scriptures as His words can be the only secure starting point for believing that any of could be true at all.