Corpses Do Not Bleed
An important piece of information is mentioned in the Gospel of John which supports the view that Jesus did not die on the cross:
"One of the soldiers pierced Jesus' side with a spear, bringing a sudden flow of blood and water" (John 19:34).
Blood pouring out is a sign of intact circulation, with the spear injuring an arteriole. Note the words 'sudden flow' which implies blood pressure. The 'water' was perhaps pleural fluid, present between the rib cage and lungs.
As blood does not rush out of corpses, the quoted verse did present a problem to at least one Church Father, Origen. In his exegesis of John 19:34, he admitted that blood coagulates after death, but the flow of blood in this case constituted a miracle and thus needed no explanation. (Contra Celsus, by Origen, translated by H. Chadwick, Cambridge U).
The spear thrust into the side of Jesus was not meant as a kind of definitive blow, but as a rough (and actually inaccurate) indicator if death had occurred. If the intent were to kill, the soldier would have stabbed into the front of the chest to injure the heart. However, in the event the person was not on the cross for sufficient length of time, death was usually caused by breaking the legs, as was done with the individuals hanging along side Jesus.
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