Once again I find my self inspired to answer this question, Why did God feel it necessary to hang himself upon the cross?
Because he is in complete control and that means that he caused the unbalancing of the scales himself; by causing Adam to eat the fruit of the tree of the knowledge of good and evil, which led to the death of men. To even the score he had to cause his own death and then offer it as a point of a free gift to anyone who would accept forgiveness.
All you have to do is believe that Jesus was God and that by his death on the cross we are plainly forgiven.
Jesus says only believe and you shall be saved.