What does John 19:18 mean?

John's description of this event is concise, masking the brutality involved. Roman crucifixion was so shameful and barbaric that Roman citizens were exempt from it. Victims were usually stripped naked (John 19:23) and forced to carry at least the horizontal beam to the execution site (John 19:17). This site was frequently chosen for visibility, maximizing witnesses. The process, itself, was much more precise than what's often depicted in artwork and modern popular culture. When everything went as intended, a crucifixion victim would languish in indescribable agony for as long as several days. Eventual death came through exposure, suffocation, or blood loss. This horrific process inspired the English term for maximum pain: "excruciating," from a Latin reference to crucifixion.

Crucifixion victims could be nailed through the palms of the hands, but the more common location was just above the wrist, between the bones of the forearm. Wide-headed spikes, slightly thinner than a finger, and about length of the hand, would pierce a major nerve, resulting in constant agony. This would also avoid major blood vessels, prolonging the pain, and provide enough support for the weight of the body. Similar attention was given to the feet: attached through a major nerve, not a blood vessel, and allowing for weight to hang. Most victims were nailed with slightly bent legs and widespread arms. Mass crucifixions sometimes resulted in bored executioners using more bizarre positions.

Normal crucifixion posture left the victim's weight hanging by the two wrists, pulling the chest wide and making it hard to breathe outwards. To breathe properly, the victim had to pull against the wrist nails or push against the foot nails. Using the legs was much easier, but both were brutally painful. There they would hang, exposed to weather, wild animals, infection, thirst, and constant agony. Eventually, one or all those would cause death. Most commonly, the victim would tire of struggling to breathe, lose the ability to lift against the nails, and slowly suffocate. This could take several days, after which the body was often left to rot as a public spectacle.

Breaking the shins of a crucified victim would greatly accelerate the process. This would make it impossible for them to push with the legs, eliminating the ability to properly breathe, causing suffocation within several minutes. Jesus' death will come in a matter of hours, even without such measures. The scourging He suffered from Pilate's men (John 19:1) would have made Him weak, already suffering serious blood loss. By the time executioners tend to the other condemned men (Isaiah 53:2), Jesus will be dead (John 19:31–33).