What does Matthew 8:15 mean?

Jesus has just entered Peter's house in Capernaum, where they found Peter's mother-in-law lying down, sick with a fever (Matthew 8:14). Apparently without hesitating, or even being asked, Jesus immediately touched her hand and healed her. Once again, Jesus breaks with Jewish convention. His actions contradict social norms of that era.

First, He touches a woman, something many of Israel's religious leaders refused to ever do for any reason to avoid even the appearance of inappropriateness. Second, touching someone who was sick or had a fever was thought to make the person who did the touching unclean. Jesus, though, did not become ceremonially unclean; the woman stopped being sick the moment he touched her. The same thing happened in the case of the man with leprosy (Matthew 8:3).

In all these cases where Jesus seems unconcerned about Jewish convention, He never breaks the actual Law of Moses. He remains sinless (Hebrews 4:15). Instead, He shows that human traditions later added to the Law as customs were not, in fact, binding. Whatever the intention, those customs and traditions often created an unnecessary burden for the Jewish people (Matthew 23:4).

Peter's mother-in-law was instantly healed. Instead of needing time to recover from her fever, as would be natural, she immediately got up and started to fulfill her role as a hostess in the household, serving Jesus and the others. Her ability to do so is evidence that the healing was supernatural.