When the women go to anoint Jesus' body right after the Sabbath, they are shocked to find it gone. They go tell the disciples that the Jews or Romans (or grave robbers?) took His body. Peter and John run to investigate and find the linen cloth still there and the head piece folded neatly. It can't be robbers. John is convinced He's alive, but Peter isn't sure, and they go home. Mary stays and sees angels over the bier in the same position as the ark. They ask why she is weeping, and Jesus appears. She still doesn't recognize Him until He says her name.
That night He appears to the disciples and gives them a (fore?)taste of the Spirit. Thomas wasn't there and won't believe it until he sees it for himself. Jesus gives him what he asks but blesses those who follow who don't make his demand.
Jesus really was alive and out of the tomb after His crucifixion and burial.
We are slow to believe good things God does for us, because He likes to go beyond the usual way of doing things.
We must not insist on first hand experience to believe the apostles' witness.