I will have mercy, etc. - See this explained, Matthew 9:13.

There are four ways in which positive laws may cease to oblige.

First, by the natural law of necessity.

Secondly, by a particular law, which is superior.

Thirdly, by the law of charity and mercy.

Fourthly, by the dispensation and authority of the Lawgiver.

These cases are all exemplified from Matthew 12:4-8.

But if ye had known what this meaneth, The passage of Scripture in Hosea 6:6

I will have mercy, and not sacrifice; of the sense of which, see Gill on Matthew 9:13.

ye would not have condemned the guiltless. Our Lord taxes the Pharisees both with ignorance of the Scriptures, in which they pretended to be very knowing, and took upon them to be the interpreters of; and with inhumanity, for condemning innocent persons, the apostles, for rubbing a few ears of corn, for the refreshment of nature; which they would never have done, had they understood the word, and will of God; who prefers acts of humanity, compassion, and mercy, to the observance of rites and ceremonies; or had they the common affections of human nature, and those bowels of compassion which one man ought to show to another.

But if ye had known what this meaneth, I will have mercy, and not sacrifice, ye would not have condemned the guiltless.

12:7 But if ye had known what this meaneth. They ought to have known, for they professed to be interpreters of the law.

I will have mercy, and not sacrifice. The argument is that mercy toward these hungering disciples was more acceptable to God than sacrifices at the altar, though sacrifice was the crown of the Jewish rites. The quotation is from Ho 6:6, and is also quoted in Mt 9:13. It shows that all our forms, rites and ceremonies are worthless before God unless we have kind and merciful hearts.

12:7 I will have mercy and not sacrifice - That is, when they interfere with each other, I always prefer acts of mercy, before matters of positive institution: yea, before all ceremonial institutions whatever; because these being only means of religion, are suspended of course, if circumstances occur, wherein they clash with love, which is the end of it. Matt 9:13.

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 [1270]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.

12:1-8 Being in the corn-fields, the disciples began to pluck the ears of corn: the law of God allowed it, De 23:25. This was slender provision for Christ and his disciples; but they were content with it. The Pharisees did not quarrel with them for taking another man's corn, but for doing it on the sabbath day. Christ came to free his followers, not only from the corruptions of the Pharisees, but from their unscriptural rules, and justified what they did. The greatest shall not have their lusts indulged, but the meanest shall have their wants considered. Those labours are lawful on the sabbath day which are necessary, and sabbath rest is to froward, not to hinder sabbath worship. Needful provision for health and food is to be made; but when servants are kept at home, and families become a scene of hurry and confusion on the Lord's day, to furnish a feast for visitors, or for indulgence, the case is very different. Such things as these, and many others common among professors, are to be blamed. The resting on the sabbath was ordained for man's good, De 5:14. No law must be understood so as to contradict its own end. And as Christ is the Lord of the sabbath, it is fit the day and the work of it should be dedicated to him.