NOTES for Ti2 3:16
The God-breathed character (that is, inspiration by God) of Scripture is one of the foundations of the Christian faith. And since this is faith, there is no point in looking for proofs that it is so, because in matters of faith what works is not proofs but testimonies. And here we read such a testimony in the Bible itself. But can such testimony be trusted when someone says something good about himself?
This situation was already described in the eighth chapter of the Gospel of John (vv. 12-18), when the Pharisees told Jesus that since He was bearing witness about Himself, His testimony was not true. Jesus' answer overturns all ordinary ideas: the words a person speaks do not tell us about his "quality"; rather, the person's "quality" gives weight to his testimony.
So it is here as well: the level of truth in the Bible is such that this self-testimony is not even necessary, and the meaning of Paul's statement is different. The emphasis should be placed on the word "all." Scripture is not torn into pieces, some of which are useful for teaching, others for reproof, and so on. No, Scripture is whole, and it is precisely this wholeness that corresponds to the God-breathed character of the Message carried by the Bible. This Message, which cannot be broken down into separate verses, is the Word of God.