Jesus over the sabbath
The Son of Man is a title Jesus used for himself. Jesus is superior to David, the priests, and the Temple. He reigns even over the Sabbath.
something greater. The Sabbath points to Christ (see v. 8) and to the “rest” he gives from the impossible task of earning salvation by good works (cf. 11:28).
the Son of Man is lord of the Sabbath. Jesus does not challenge the Sabbath law itself but rather the Pharisees’ interpretation of it. As Messiah, Jesus authoritatively interprets every aspect of the law (cf. 5:17–48) and here points out the Pharisees’ blindness to the actual intent of the Sabbath—to bring rest and well-being. This final argument in response to the Pharisees’ challenge (12:2) is the decisive argument—that because of who Jesus is, he has the authority to interpret the law.
Since Jesus is the Lord of humanity (Phil 2:9–11; Eph 1:20–22; 1 Cor 15:25–28) and since the Sabbath was made to meet the needs of people (see notes on Matt 12:3–7), he is Lord … over the Sabbath. As with Jesus’ authority to forgive sins (2:7), this was a claim to divine authority.
The Sabbath was made for man. God instituted the Sabbath to benefit man by giving him a day to rest from his labors and to be a blessing to him. The Pharisees turned it into a burden and made man a slave to their myriad of man-made regulations.