Luke 24:1-7 (NKJV)
Now on the first day of the week, very early in the morning, they, and certain other women with them, came to the tomb bringing the spices which they had prepared. But they found the stone rolled away from the tomb. Then they went in and did not find the body of the Lord Jesus. And it happened, as they were greatly perplexed about this, that behold, two men stood by them in shining garments. Then, as they were afraid and bowed their faces to the earth, they said to them, "Why do you seek the living among the dead? He is not here, but is risen! Remember how He spoke to you when He was still in Galilee, saying, 'The Son of Man must be delivered into the hands of sinful men, and be crucified, and the third day rise again.' "
When Jesus rose from the dead, He proved that He is the Son of God just as He said. The leaders who were opposed to Jesus knew that he had prophesied his resurrection on the third day. They figured in their minds that Jesus' disciples would try to steal His body and then claim he had risen from the dead. Knowing this, they posted guards at Jesus' tomb for the express purpose of preventing this. All that it would take to prove that there was no resurrection would be to produce Jesus' body. They could not do that, because He is alive!