Who killed Jesus? There are many possible culprits the investigation must consider. The most obvious would be the Roman powers. Lots of eye-witnesses would have been able to identify the soldiers who hammered in the nails. Probably their defense would have been, "I was only doing my job; I was following orders." At the top of the hierarchy, Pilate might have argued "The people made me do it!", so our investigation broadens out.
A good case could be made for the religious leaders being the cause of Jesus' death. It all worked out according to their plan when they handed Jesus over to Pilate. But behind them was a nation of culpable people, for it was the whole crowd who fanatically demanded of Pilate, "Crucify him!" Peter seemed to place the blame here, for when he preached at Pentecost he spoke to the crowds of the Jesus whom "you you have crucified and put to death" (Acts 2:23). But if you are looking for a particular scapegoat, then surely we could hold Judas responsible for Jesus' death?
If you dig in the archives for the background of the story, you could make a case for Adam being the cause of death. But in acknowledging that we are all admitting our own guilt, for we have our father's genes, and Jesus' death would never have happened if it were not for our sinfulness. I cannot point the finger to Adam or to Pilate; I killed Jesus, and continue to do so with every sin I commit. Though where Pilate says that the people made him do it, Adam or I may be tempted to plead, "The devil made me do it." This argument doesn't let us off the hook, but it has a point. Surely Satan is on our list of suspects, for it was he who instigated the whole scheme that culminated in the death of the Son of God.
But ultimately the responsibility for the death of Christ rests on one who has remained above suspicion in all the investigation outlined above. Nobody would have ever suspected him, but there is one crucial piece of evidence we have so far overlooked. The Peter who accused the Jerusalem mob of killing Jesus also, in the same breath, spoke of him being put to death by "the determined purpose and foreknowledge of God." Here's the mastermind behind all these secondary agents. And if we pursue this line of inquiry it takes us back to the incontrovertible evidence of Isaiah 53:4-10 where we read:
Surely he has borne our griefs and carried our sorrows; yet we esteemed him stricken, smitten by God, and afflicted...And the Lord has laid on him the iniquity of us all ...Yet it pleased the Lord to bruise him; He has put him to grief.
It was God who killed him! The ultimate example of friendly fire. Killed by the one who loved him the most. Caught in the cross hairs of the Father's fire. But, unlike contemporary examples of friendly fire, it was not a mistake. It was a carefully thought-out plan in which the Son of God willingly co-operated. The only way. The Good Friday way. The Son enduring the Father's friendly fire so that the sons would not have to endure the fearful fire of the Father's eternal wrath. "The chastisement for our peace was upon him."