If you look up blog posts and journal articles and books about 2 Timothy 3:16-17, you’ll find alot of discussion about inspiration, infallibility, and inerrancy. There are important discussion, but I don’t think Paul wrote that passage to Timothy in order to answer those questions.
First, look at the passage again:
All Scripture is breathed out by God and profitable for teaching, for reproof, for correction, and for training in righteousness, that the man of God may be competent, equipped for every good work. (2 Timothy 3:16-17 ESV)
Yes, Paul mentions “inspiration” (literally, “God-breathed”), but he uses it as an adjective to describe Scripture. He does not argue for inspiration.
So, why did Paul write this sentence to Timothy? To show one of the purposes of Scripture. What purpose?
Paul tells Timothy that Scripture can be useful for teaching, correcting, rebuking, and training in righteousness. But, teaching, correcting, rebuking, and training in righteousness is the “end” or “goal” for Paul. These are means to the goal.
What is that goal? So that God’s children (“man” does not refer to “males” here, but to people in general) may be prepared for good works. Did you catch that? The goal of teaching is not to be educated. The goal of correcting is not to be correct. The goal of rebuking is not to be straightened out. The goal of training is not to be able.
The goal of all of these things is good works.
If we teach people Scripture so they can quote, and correct their understanding using Scripture, and rebuke them where they’re wrong using Scripture, and train them in what Scripture says… if we do all these things, we have not used Scripture in the way that Paul intended it in this passage. Instead, the goal of teaching, correcting, rebuking, and training is that God’s children would do good works.
So, one of the purposes of Scripture is good works.
Of course, this should not surprise us, since good works is also the purpose of our mutual encouragement. Remember this passage from Hebrews?
And let us consider how to stir up one another to love and good works… (Hebrews 10:24 ESV)
We shouldn’t be afraid of good works. No one is saved by their works, but that does not mean that good works are not important. They are extremely important. In fact, we all know that James says that faith without works is dead. This is usually contrasted with Paul’s teaching about salvation by grace through faith, but the contrast is not valid:
For by grace you have been saved through faith. And this is not your own doing; it is the gift of God, not a result of works, so that no one may boast. For we are his workmanship, created in Christ Jesus for good works, which God prepared beforehand, that we should walk in them. (Ephesians 2:8-10 ESV)
Paul writes about grace and faith, but also good works.
So, if you as a child of God want to learn Scripture, see that it leads to good works. If you want to understand Scripture, see that the understanding leads to good works.
Why? Because one of the purposes of Scripture is to lead God’s children toward doing good works.