matthew 12:7 But if ye had known what this meaneth, I will have mercy, and not sacrifice, ye would not have condemned the guiltless. - Free Bible Online

      7. But if ye had known what this meaneth, I will have mercy, and not sacrifice-- (Ho 6:6; Mic 6:6-8, &c.). See on Mt 9:13.
      ye would not have condemned the guiltless--that is, Had ye understood the great principle of all religion, which the Scripture everywhere recognizes--that ceremonial observances must give way before moral duties, and particularly the necessities of nature--ye would have refrained from these captious complaints against men who in this matter are blameless. But our Lord added a specific application of this great principle to the law of the sabbath, preserved only in Mark: "And he said unto them, the sabbath was made for man, and not man for the sabbath" (Mr 2:27). A glorious and far-reaching maxim, alike for the permanent establishment of the sabbath and the true freedom of its observance.

JFB.