The next day, that is, after the Preparation, the chief priests and the Pharisees gathered before Pilate and said, "Sir, we remember how that imposter said, while he was still alive, 'After three days I will rise.' Therefore order the tomb to be made secure until the third day, lest his disciples go and steal him away and tell the people, 'He has risen from the dead,' and the last fraud will be worse than the first." Pilate said to them, "You have a guard of soldiers. Go, make it as secure as you can." So they went and made the tomb secure by sealing the stone and setting a guard. Matt. 62-66, ESV.
Here we find a passage full of surprises. The first is the fact that it is the Jewish leaders who remember that Jesus had promised to resurrect after His death. The disciples had completely overlooked that prediction even though Jesus had repeatedly told them He would die and be resurrected (see Matt. 16:21; 17:23; 20:19; 12:40).
What they forgot, and apparently never even really heard, the Jewish leaders would remember, even though they did not believe it would take place. Rather, they feared that the disciples would steal the body and claim a resurrection. In that case, their lie concerning Jesus' resurrection would be worse than His lie that He was the Messiah.
The passage's second great surprise is that the Jewish leaders were so worried about that possibility and the crisis that would flow out of it that they take the unprecedented step of breaking their own extremely rigid Sabbath laws by visiting Pilate (an unclean Gentile) on their holy day to request a guard for Jesus' tomb. That breach of their unusual practice indicates the depth of their fear of the dead man's disciples perpetrating a hoax. The Jewish establishment was willing to do anything to put an end to the Jesus problem.
Pilate's mind must have reeled as these events unfolded. But, presumably tired of the whole business, the governor readily agrees to cooperate with the troublesome leaders, since if he doesn't, and the body is gone on the third day, there will be no end to the problem. He thus grants the Jewish leaders a guard to seal the tomb and watch over it.
But in taking such precautions, Leon Morris points out, the Jewish leaders "did more than they knew. They ensured that there could be no nonsense about disciples stealing the body when in due course Jesus did rise from the dead. The precautions of his enemies would underline the truth of his resurrection."
Strange indeed are the wonders of God's providence. God can use anyone or anything to bring about His purposes on the stage of earth's history.