Jesus and the thief

Jesus, crucified on the cross, cried out: "My God, My God, why hast thou forsaken me?"
Then Jesus said to the thief crucified along side Him: "Verily, I say unto thee, "today shalt thou be with me in paradise." The thief could not believe his ears. How can a duly forsaken relative of God promise to paradise to any one? Poch suzara