He died to atone for the original sin in the Garden of Eden. He bore our sins and broke free of mans curse of death. He had to suffer and die so that he could save us from eternal death.
When God created the garden and put man in it there was a perfect relation ship between God and man. It stayed as a perfect relationship until the serpent came and deceived them into eating the forbidden. So Adam and Eve were cast out of the garden. This original sin is passed down from generation to generation so none are right with God from birth. Also because of this sin Men have to work they land and eat by the sweat of their brow. Women have greatly increased child pains because of it as well. Both men and women have to die also.
God sent his son Jesus so that we may not have to suffer eternal death. On the cross Jesus reconciled our sin on to him and died to atone for our sins as the perfect sacrifice. When he died he went to hell for three days then arose from the dead. This symbolizes that he broke the punishment of man when Adam was removed from the garden.
Jesus saved us from our eternal punishment for the sin in the garden. He had to do this in order that we might be with him eternally instead of separated from life eternally.He had to suffer and die so that we would be able to have life eternal.