New Defender's Study Bible Notes
4:12 despise thy youth. Youth should not be a time for sowing wild oats, but of using one’s youthful strength in living and witnessing for Christ, serving as an example and encouragement even to older believers, who may have grown lethargic in Christ’s service. Christian young people should not only “flee youthful lusts” (II Timothy 2:22) but especially, in view of the dominance of evolutionism in modern education, “remember now thy Creator in the days of thy youth” (Ecclesiastes 12:1).
4:12 conversation. That is, “manner of life.”