Only the resurrection of Jesus from the dead can explain why Christians believed Jesus was divine.  It also gives credence to the fact that Jesus claimed to be God.

Many skeptics think that Jesus never made claims to deity – that such claims were merely put on his lips by his followers.  But why would they do so?  The Jews had no concept of a divine messiah.  Indeed, the idea that God could become a human being was considered blasphemy to the Jews.  If the gospels are to be believed, the reason Jesus was condemned to death by the Jews was precisely because he claimed to be God.

Given Jewish theological beliefs, why would the disciples proclaim Jesus as God?  It surely wouldn’t win them any fans among the Jews!  Some say they came to believe Jesus was divine because they came to believe that Jesus was resurrected from the dead, but there is no logical connection between the two.  One need not be God to experience resurrection.  Indeed, most Jews expected to experience resurrection in the future, so a resurrection in itself wouldn’t cause the disciples to believe Jesus was divine.  The best explanation for their claim is that Jesus Himself made such claims while alive.  The disciples understood Jesus’ resurrection to be God’s vindication of Jesus, and hence a verification of Jesus’ claims.  In other words, Jesus’ resurrection proved that Jesus was who He claimed to be, and since He claimed to be God, the disciples proclaimed Him to be God as well.