Jesus turned the accusation back on the accusers. They asked why His disciples "transgress" a tradition; He asked why they "also transgress" a commandment of God. The little word "also" sets the two side by side and shows which is more serious. Gill puts it this way: the disciples, "at most, were but guilty of the breach of an human precept," while the Pharisees broke a divine command. Barnes adds that Jesus was implying His disciples were not bound by traditions "invented by human beings," especially traditions that set aside the plain laws of God.

Jesus answered His own question with a specific case. God said, "Honour thy father and mother" (Matthew 15:4). But the tradition allowed a son to say of his goods, "It is a gift," and then "honour not his father or his mother" and be "free" (Matthew 15:5-6). Jesus concluded, "Thus have ye made the commandment of God of none effect by your tradition," called them "hypocrites," and applied Isaiah's words to them (Matthew 15:6-9). No reply from the scribes and Pharisees is recorded, but the disciples soon reported that the Pharisees "were offended" (Matthew 15:12).

Mark gives the word Jesus used for the gift: "Corban, that is to say, a gift" (Mark 7:11). Barnes explains that corban was a Hebrew word for something dedicated to God's service and set apart from any other use. Under the tradition, a son could declare his property corban, and he was then counted free from using it to support a needy parent. Barnes notes that the law did require vows to be kept (Psalm 76:11; Deuteronomy 23:21), which is how the tradition could look like piety while canceling the fifth commandment.

Jesus quoted both Exodus 20:12 and Exodus 21:17, "he that curseth his father, or his mother, shall surely be put to death." In Greek, "transgress" in Matthew 15:2 and Matthew 15:3 is the same verb, parabainō, which Thayer defines as to overstep or violate.

This question shows that God's commands cannot be overruled by religious rules, even rules that sound devout. God had tied honor for Him to honor for parents, and no vow could make the second unnecessary. Mark records Jesus adding, "many such like things do ye" (Mark 7:13), so the Corban rule was one example of a wider pattern.

Barnes is careful to say that Jesus did not condemn giving to God; He praised the poor widow who gave all she had (Mark 12:44). What He condemned was giving used to get out of a duty God had commanded. Matthew Henry draws the lesson: "Never let us think that the religion of the Bible can be improved by any human addition, either in doctrine or practice."