What does Matthew 9:26 mean?

Jesus has just restored a girl—understood by all observers to be dead—back to life. He simply took her by the hand, told her to rise, and she did.

This is perhaps Jesus' greatest miracle so far. It connects Him to the prophets Elijah (1 Kings 17:17–24) and Elisha (2 Kings 4:17–37), who were both used by God to raise to life children who had died. The difference between them and Jesus was that neither Elijah nor Elisha claimed to the Messiah, the Son of God. Jesus will again raise the dead, in even more dramatic fashion and before far more witnesses, when His friend Lazarus is resurrected (John 11).

Mark and Luke conclude the story of Jesus raising this girl to life by quoting Jesus as telling her parents to give her some food and then instructing them to tell no one about this (Mark 5:43; Luke 8:56). Either these amazed parents disobeyed that command or the mourners who had been removed figured it out. According to this verse, the report of this girl's return to life spread through the entire district.

Jesus likely asked the parents to keep the miracle quiet because the crowds following Him were already nearly unmanageable. Jesus' mission was to die for the sins of humanity, not to lead a revolution against the Romans. If the crowds following Him became too frenzied, it might bring trouble with the Romans sooner than He was planning (John 6:15). Still, Jesus' commands to keep quiet about miraculous events rarely kept news from getting out.