The apostles believed slowly that Jesus had risen from the dead, although those men knew the Scriptures, which also spoke of the suffering and the resurrection of the Messiah,

Then He said to them, “These are the words which I spoke to you while I was still with you, that all things must be fulfilled which were written in the Law of Moses and the Prophets and the Psalms concerning Me” (Luke 24:44).

The Law, the Prophets, and the Psalms, the entire Old Testament spoke of Jesus, and everything that it said of Him, He fulfilled, because Jesus is the Christ, the Son of the living God.