3:8-11 When the grace of God towards mankind has been declared, the necessity of good works is pressed. Those who believe in God, must make it their care to maintain good works, to seek opportunities for doing them, being influenced by love and gratitude. Trifling, foolish questions must be avoided, and subtle distinctions and vain inquiries; nor should people be eager after novelties, but love sound doctrine which tends most to edifying. Though we may now think some sins light and little, if the Lord awaken the conscience, we shall feel even the smallest sin heavy upon our souls.
8. Greek, "faithful is the saying." A formula peculiar to the Pastoral Epistles. Here "the saying" is the statement (Tit 3:4-7) as to the gratuitousness of God's gift of salvation. Answering to the "Amen."
these things, &c.—Greek, "concerning these things (the truths dwelt on, Tit 3:4-7; not as English Version, what follow), I will that thou affirm (insist) strongly and persistently, in order that they who have believed God (the Greek for 'believed in God' is different, Joh 14:1. 'They who have learnt to credit God' in what He saith) may be careful ('Solicitously sedulous'; diligence is necessary) to maintain (literally, 'to set before themselves so as to sustain') good works." No longer applying their care to "unprofitable" and unpractical speculations (Tit 3:9).
These things—These results of doctrine ("good works") are "good and profitable unto men," whereas no such practical results flow from "foolish questions." So Grotius and Wiesinger. But Alford, to avoid the tautology, "these (good works) are good unto men," explains, "these truths" (Tit 3:4-7).