Matthew 12:3

(Quæst. in Matt. q. 10.) It should be observed, that one example is taken from royal persons, as David, the other from priestly, as those who profane the sabbath for the service of the Temple, so that much less can the charge concerning the rubbing the ears of corn attach to Him who is indeed King and Priest.

Then it proceeds to their excuse; But he said unto them, Have ye not read what David did, when he was an hungred? To refute the false accusation of the Pharisees, He calls to mind the ancient history, that David flying from Saul came to Nobba, and being entertained by Achimelech the Priest, asked for food; (1 Sam. 21.) he having no common bread, gave him the consecrated loaves, which it was not lawful for any to eat, but the Priests only and Levites; esteeming it a better action to deliver men from the danger of famine than to offer sacrifice to God; for the preservation of man is a sacrifice acceptable to God. Thus then the Lord meets their objection, saying, If David be a holy man, and if you blame not the high-priest Achimelech, but consider their excuse for their transgression of the Law to be valid, and that was hunger; how do ye not approve in the Apostles the same plea which you approve in others? Though even here there is much difference. These rub ears of corn in their hands on the sabbath, those ate the Levitical bread, and over and above the solemn sabbath it was the season of new moon, during which when sought for at the banquet he fled from the royal palace. Observe that neither David nor his servants received the loaves of show-bread, before they had made answer that they were pure from women.

(Ver. 3, 4.) But he said to them: Have you not read what David did when he was hungry, and those who were with him: how he entered the house of God and ate the bread of the Presence, which it was not lawful for him to eat, nor for those who were with him, but only for the priests? To refute the slander of the Pharisees, he recalls an old story, when David, fleeing from Saul, came to Nob and was received by the priest Ahimelech. He asked for food, and since he did not have any ordinary bread, Ahimelech gave him the consecrated bread, which only the priests and Levites were allowed to eat. And he merely asked if there were any boys in the world born of women; and when he responded, without hesitation, he did not hesitate to give bread, deeming it better to free people from the danger of hunger, as the prophet says: 'I desire mercy, not sacrifice' (Hosea 6:6), rather than to offer sacrifice to God. For a merciful offering is pleasing to God and the salvation of humanity. Therefore, the Lord opposes and says: 'If even David, who is holy, and Ahimelech the high priest, are not condemned by you, but rather both have transgressed the command of the Law with a justifiable excuse, and hunger is the cause, why do you not approve the same hunger in the apostles, which you approve in others?' Although there is a great difference in this. Those people rubbed the ears of grain in their hands on the Sabbath, while others ate the Levitical loaves and came near the feast of the New Moon, on which day he was sought for at the banquet and fled from the royal court. Note that neither David nor his servants took the showbread before they answered that they were clean from women.