What does Matthew 12:23 mean?

Jesus has just healed a demon oppressed man who could not see or speak, likely by removing the demon from him (Matthew 12:22). Suddenly, the man spoke and saw. The change must have been dramatic, because Matthew reports that the crowd was amazed.

In some cases, people react to Christ's miracles with fear (Mark 5:14–17) or awe (Matthew 8:26–27). This time, the people connect their amazement with the possibility that Jesus might be the long-promised Messiah: the Savior of Israel. They ask each other, "Can this be the Son of David?" The name "Son of David" was a title reserved for the Messiah. It came from God's promise to David to establish his throne over Israel forever (2 Samuel 7:16).

Because of Isaiah's prophecies, many Israelites likely associated the time of the Messiah's coming with the healing of the blind, the deaf, the lame, and the mute (Isaiah 35:5). Jesus had accomplished all those miracles and many more. Those who witnessed this healing made the correct connection between Jesus' power and the idea that He might be the Messiah.

Not everyone who witnesses this will be so reasonable. Some are so committed to disbelief (John 5:39–40) that they'll explain the supernatural act as coming from Satan (Matthew 12:24).