What does Matthew 27:64 mean?
Jerusalem's religious leaders are worried that Jesus' disciples might continue to tell people He is the Messiah. Even though Jesus is dead (Matthew 27:50), they remember hearing Jesus say He would rise from the dead after three days (John 2:19–22). Their concern is that His followers will steal the body and then go around telling everyone Jesus is alive. The priests and scribes insist such fraud would cause even more problems than would a still-living Jesus.The Pharisees and priests know it is impossible to crucify someone who is already dead. It's also not possible to persecute a person who exists only in the minds of His followers. They could not reveal a ghost to be an impostor. How could they argue with a false resurrection if there is no body? Their plan is to ask the Roman government to officially seal the tomb and guard it. That will make it secure from any tampering and retain Jesus' body as proof that He was false (Matthew 27:62–63).
Though Pilate is hardly interested in religious squabbles (John 18:29–31), he will recognize the danger and agree to post a guard (Matthew 27:65–66).