From Matthew 27: 62-64 New American Standard Bible:
62 Now on the next day, the day after the preparation, the chief priests and the Pharisees gathered together with Pilate,
63 and said "Sir, we remember that when He was still alive that deceiver said, 'After three days I am to rise again.'
64 "Therefore, give orders for the grave to be made secure until the third day, otherwise His disciples may come and steal Him away and say to the people, 'He has risen from the dead,' and the last deception will be worse than the first."
Verses 65-66 tell us Pilate orderd a guard to the tomb and told them to make it secure and put a seal on the stone.
A little historical background: The Romans conquered Judea in 63 B.C. and imposed a regional government. The Romans governed the region first through King Herod and his successors, then through prefects (such as Pontius Pilate in Jerusalem.) The Romans interest in Judea and Jerusalem was in having a stable and friendly area near Persia, Rome’s rival.
Being the prefect of Judea was not a good job to have. The Romans regarded Judea as a land inhabited by barbarians with a strange religion. A prefect had very few troops. The prefect left the day-to-day running of Judea and Jerusalem to the Jewish high priest. A prefect's most crucial role was to maintain law and order. Pontius Pilate was the prefect of Judea from 26 to 36 A.D.
The Romans appointed the Jewish high priest and he did what the Romans wanted because if he didn't, he was quickly replaced. The high priest and the chief priests (the Sanhedrin) were pawns of the Roman government. The Roman guard maintained order in the temple and with the Jewish people. When verse 65 says Pilate told the chief priests and Pharisees they could have a guard, this meant a group of highly trained Roman soldiers. It was more than two soldiers because Matthew 28:11 says "some of the guard" and "soldiers" reported what had happened.
Jesus' tomb was secured with a large stone by rolling it in a groove downhill to the tomb entrance. It would have taken several men to roll this stone up the groove to open it. The highly disciplined Roman soldiers would have faced death if they had not performed their duty. If the guard had been sleeping, they surely would have heard the stone being rolled uphill by several men.
And at this point in the historical account the disciples were in hiding after the crucifixion of Jesus. Surely they were grieved at the death of their Lord and afraid they would be next. No reasonable person would say they had stolen His body.
What is so remarkable to me about Matthew 27:62-66 isn't so much the securing of the tomb, but it is what the chief priests and Pharisees say at the end of verse 64.
"... otherwise His disciples may come and steal Him away and say to the people, 'He has risen from the dead,' and the last deception will be worse than the first."
The last deception will be worse than the first? What was the first deception? They are referring to Jesus claiming to be the Messiah, the Son of God. So they had Him crucified to put such nonsense away once and for all. But Jesus also claimed He would rise on the third day. The chief priests and Pharisees wanted the tomb guarded so the disciples could not steal the body and say the Messiah had risen.
The problem with their plan was the first claim by Jesus was not a deception and was not nonsense. Jesus is the Messiah.
It is Saturday, but Easter Sunday is coming.
He is risen!