The Pharisees saw the disciples picking and rubbing grain and called it work on the sabbath. Their question is really an accusation: "that which is not lawful." Barnes, on Matthew's account, notes that "on any other day this would have been clearly lawful," because the law allowed anyone who came into a neighbor's standing corn to pluck the ears by hand (Deuteronomy 23:25). As Dr. Thomson, quoted by Barnes on Luke 6:1, says, "The Pharisees did not object to the thing itself, only to the time when it was done."

Luke says they spoke to the disciples ("said unto them"), while Matthew and Mark say they spoke to Jesus (Matthew 12:2; Mark 2:24). Gill brings these together: "no doubt but they said it to both, first to one, and then to the other."

Jesus answered for His disciples with a question from Scripture: "Have ye not read so much as this, what David did, when himself was an hungred" (Luke 6:3). He reminded them that David went into the house of God, ate the shewbread, and gave it to his men, though it was lawful only for the priests (Luke 6:4). Then He declared, "That the Son of man is Lord also of the sabbath" (Luke 6:5). Gill calls this declaration "a full answer to their cavils."

The Law of Moses allowed plucking grain by hand from a neighbor's field: "thou mayest pluck the ears with thine hand; but thou shalt not move a sickle" (Deuteronomy 23:25). So the act itself was not theft. The Pharisees' objection was that plucking and rubbing grain counted as work on the sabbath.

Luke dates this "on the second sabbath after the first" (Luke 6:1). Barnes admits the phrase is "exceedingly difficult of interpretation" and favors Scaliger's view as "the most natural and easy explanation": it was the first sabbath after the second day of the Passover. He adds that "corn" here means grain such as wheat or barley, not maize. The disciples rubbed the heads "in their hands" to separate the grain from the chaff.

This question sets up one of Jesus' great claims. The Pharisees asked about the law, and Jesus answered by pointing to Himself: "the Son of man is Lord also of the sabbath" (Luke 6:5). As Lord of the sabbath, Barnes says, He "had a right to direct the manner of its observance" (Barnes on Matthew 12:8).

Matthew Henry, writing on this passage, says "Jesus Christ will justify his disciples when they are unjustly censured." He also adds a caution: "Works of necessity are particularly allowable on the sabbath day; but we must take heed that we turn not this liberty into licentiousness." The scene begins a chapter of sabbath conflict that grows sharper in the synagogue (Luke 6:6-11).