15:9 In vain do they worship me. Quoted from Is 29:13. This worship is all idle, empty, and without profit, because they
teach as doctrines the commandments of men. This rebuke to the Pharisees, who had added to the law of Moses many traditional human precepts, applies equally to all modern religionists who have modified or added to the Christianity of Christ and the apostles. Whatever one cannot find in the New Testament is of such a character; observance of saints' days, of Christians, of Lent, the removal of the cup in the Lord's Supper from the laity, infant sprinkling, party creeds and party shibboleths, are all of men and not of God. The devout worshiper should go right to the New Testament for his religion, and reject every ordinance or precept that is not to be found there.
15:9 Teaching the commandments of men - As equal with, nay, superior to, those of God. What can be a more heinous sin?
15:1-9 Additions to God's laws reflect upon his wisdom, as if he had left out something which was needed, and which man could supply; in one way or other they always lead men to disobey God. How thankful ought we to be for the written word of God! Never let us think that the religion of the Bible can be improved by any human addition, either in doctrine or practice. Our blessed Lord spoke of their traditions as inventions of their own, and pointed out one instance in which this was very clear, that of their transgressing the fifth commandment. When a parent's wants called for assistance, they pleaded, that they had devoted to the temple all they could spare, even though they did not part with it, and therefore their parents must expect nothing from them. This was making the command of God of no effect. The doom of hypocrites is put in a little compass; In vain do they worship me. It will neither please God, nor profit themselves; they trust in vanity, and vanity will be their recompence.
