But abide thou in the things which thou hast learned and hast been assured of, knowing of whom thou hast learned them;
And that from a child thou hast known the holy Scriptures,.... And therefore must know that the doctrines he had learned were agreeable to them; and so is another reason why he should continue in them. The Jews very early learned their children the holy Scripture. Philo the Jew says (w), "from their very infancy"; a phrase pretty much the same with this here used.
Timothy had watched my life match my doctrine, I did not pull down by living what I built by preaching. A minister whose manner of life contradicts his teaching cannot expect to profit the people at all.
AI summary
Commenting on 2 Timothy 3:10-17
But . . . thou--Whatever they may do. Resuming the thread begun at Ti2 3:10. learned--from me and thy mother and grandmother (Ti2 1:5; Ti2 2:2). assured of--from Scripture (Ti2 3:15). of whom--plural, not singular, in the oldest manuscripts, "from what teachers." Not only from me, but from Lois and Eunice.