The Bible was written by men like Moses and Paul, but it was Holy Ghost written by God. We know that “scripture” (v.16) means the books of the Bible, for Paul quoted one of them when he asked “what saith the scripture?” (Rom.4:3).
It is taught that a third century council determined the canon of which books should be in the Bible, but Peter knew that Paul’s epistles were “Scripture” as they were being written (II Pet. 3:15,16). The prophets identified which epistles were Scripture (I Cor. 14:37).
We know no books are missing from our Bible because the Bible has 66 books and Isaiah has 66 chapters. The first chapter of Isaiah has things in it that remind you of the first book of the Bible (Isa. 1:2,9), and the last chapter has things that remind you of the last book of the Bible (Isa. 66:22; Rev.21:1). Each chapter in between in Isaiah has things that remind you of the corresponding book in the Bible.
The Greek word for “inspiration” (3:16) means God-breathed. You have to breathe out to form the words that come out of your mouth, and that’s what God did with the words that proceeded out of His mouth in the Bible (Mt. 4:4). The breath of God gives life (Gen.2:7) and the Bible is alive (Heb.4:12) and powerful enough to give life (John 6:63). When you expire the life-breath of God leaves you, so when God inspired the Bible His life breath entered the words.
People say that men wrote the Bible and not God, but one of those men said that God spoke by him (I Sam. 23:2). But they didn’t take dictation, for the Bible writers all had their own style that reflected who they were. Luke was a doctor (Col.4:14) and wrote like one (Acts 3:7). But they all spoke “as they were moved by the Holy Ghost” (II Pet. 1:21)
Inspiration is what makes God’s word “profitable” (3:16). God’s Word doesn’t profit us financially if we obey it like it did for Israel, but it can still give us the “profit” of “peace” and “righteousness” (Isaiah 48:17,18). You’ll never have peace without righteousness, by the way. It is “lying words, that cannot profit” that say that salvation delivers you to sin (cf. Jer. 7:8-10).
But the Bible is only profitable if it is rightly divided (II Tim. 2:15). If it isn’t divided at all, you’re going to think obeying God’s word will profit you as it did Abraham and Job. If it is wrongly divided between the Old Testament and New Testament, you’re going to think you’re not saved every time you sin (I John 3:9: 5:18). The Bible must be divided between Paul’s epistles and the rest of the Bible.
But the Scriptures couldn’t profit us unless God preserved them, which He promised He would (Isa. 40:8; Mt.5:18). There are no tittles in our KJV, but we know it is still God’s Word because Paul spoke God’s word in Hebrew (Acts 22:1-22) and it was still God’s word when Luke wrote it down in Greek even though it was a translation. But we know other versions are God’s Word because God knows how to use other words to say “the same words” (Mt. 26:39-44).
The Bible is profitable “for doctrine” (3:16) or teaching because it is the only thing that is sure. Peter said it was more sure than what he saw with his eyes and heard with his ears (II Pe. 1:16-19). Yet when we say God no longer gives the gift of healing, our Pentecostal friends often say He is because of something they think they’ve seen.
“Reproof” (3:16) is what you give someone who isn’t acting right. 14 of the 17 times the word appears it is used to speak of how a father reproves his son for not acting right (in Proverbs). Reproof was given to children with the rod (Pr. 29:15). “Correction” (3:16) is what you give someone who isn’t thinking right according to what you taught him (Ps. 94:10,11). Children were corrected with the rod as well (Pr.22:15).
God reproved and corrected the children of Israel with the rod (Jer. 2:19) of Babylon. But God is not reproving us to-day. We are His sons (Gal.4:6) and you correct adult sons with words. God corrects us with the words of Scripture.