5:18 Verily I say unto you. This formula always introduces a very emphatic saying. It occurs thirty times in Matthew. See notes on Mr 3:28 Lu 4:24 Joh 3:3.
One jot or one tittle. Jot means the smallest letter of the Hebrew alphabet, while tittle refers to a simple turn by which one letter is distinguished from another. The expression, jot or tittle, was proverbial for the smallest part.
Till all be fulfilled. Says Dr. Schaff,
Till implies that after the great events of Christ's life, and the establishment of his kingdom, the old dispensation, as a dispensation of the letter and yoke of bondage, as a system of types and shadows, will pass away, and has passed away (Eph 2:15 Col 2:14 Heb 8:13); while the spirit and substance of the law, i.e. love to God and man, will last forever.''
5:18 Till all things shall be effected - Which it either requires or foretells. For the law has its effect, when the rewards are given, and the punishments annexed to it inflicted, as well as when its precepts are obeyed. Luke 16:17; 21:33.
5:17-20 Let none suppose that Christ allows his people to trifle with any commands of God's holy law. No sinner partakes of Christ's justifying righteousness, till he repents of his evil deeds. The mercy revealed in the gospel leads the believer to still deeper self-abhorrence. The law is the Christian's rule of duty, and he delights therein. If a man, pretending to be Christ's disciple, encourages himself in any allowed disobedience to the holy law of God, or teaches others to do the same, whatever his station or reputation among men may be, he can be no true disciple. Christ's righteousness, imputed to us by faith alone, is needed by every one that enters the kingdom of grace or of glory; but the new creation of the heart to holiness, produces a thorough change in a man's temper and conduct.
