Charles Ellicott Commentary Matthew 12:10

"and behold, a man having a withered hand. And they asked him, saying, Is it lawful to heal on the sabbath day? that they might accuse him." — Matthew 12:10 (ASV)

There was a man who had a withered hand — Two facts are implied:

1. The Pharisees expected our Lord to heal this afflicted man. They knew that the mere sight of this kind of suffering commonly called forth His sympathy, and that this sympathy would lead to action.
2. They had resolved, if He did heal him, to make it the basis for a formal accusation before the local tribunal, the “judgment” of Matthew 5:21.

The casuistry of the Rabbis allowed the healing art to be practiced on the Sabbath in cases of life and death, but the “withered hand,” a permanent infirmity, obviously did not come under that category.