Long before the law was given by Moses, our whole race fell when Adam fell in the garden of Eden.  Adam, a representative man, sinned against God and in him “all sinned.”  (Rom. 5:12)  This is why “death reigned from Adam to Moses.”    But the penalty for sin against God is far more than physical death.  Sin cannot be reversed, it must be punished.  The penalty God requires for sin is death, a death that will satisfy divine justice.  “Behold, all souls are mine; as the soul of the father, so also the soul of the son is mine: the soul that sinneth, it shall die.” (Ezekiel 18:4)  “For the wages of sin is death...” (Rom. 6:23)  That penalty must be paid.  It cannot be paid by a sinner but requires the death of a sinless sacrifice.  Every picture in the Old Testament sacrifices shows this.  Christ, if He be that “one sacrifice for sins forever,” must be such.  If He be our Substitute, He must do the one thing God could not do from heaven, He must die.  If you think of all that God did, can do and does from heaven, the one thing necessary to our salvation He could not do which is to die in our place.  To do this He must become a man, take upon Himself a body and in that perfect body die as the Substitute for His sheep.  “I lay down my life for the sheep.”  Our death can only be because of our sin.  His death as One who knew no sin, is for sin.  We are not called upon to try and enter into the depths of His sufferings.  How could we who have known nothing but sin enter into the sufferings of Him who never knew sin?  No, we are simply called upon to look to His death.  To rest in what He accomplished for us as our Substitute.  If He died for me the death required for my sin, I don’t have to die.  All He suffered, I do not know but I know He suffered all that was due me.  My Substitute died in my place and I am a participant in His sufferings not because of what I feel about them but because God in grace views me “in Christ.”  When He died for my sin, I died to sin.  His death is the source of my life.  This is the gospel emphasis: “Who is he that condemneth? It is Christ that died, yea rather, that is risen again, who is even at the right hand of God, who also maketh intercession for us.” (Romans 8:34)  Christ “died for the ungodly.” God commeneth His love toward  us in that while we were yet sinners Christ died for us.  We were “justified by His blood.”  We were “reconciled to God by the death of His Son.”  I don’t expect to ever know the fulness of my Substitute’s sufferings or be able to feel the depth of His agonies.  But this is know because God has declared it, Christ my Substitute died in my place!  “I need no other argument, I need no other plea, It is enough that Jesus died,  And that He died for me.”