Albert Barnes Commentary John 19:34

"howbeit one of the soldiers with a spear pierced his side, and straightway there came out blood and water." — John 19:34 (ASV)

One of the soldiers. One of those appointed to watch the bodies until they were dead. This man appears to have doubted whether he was dead and, to determine if he was still conscious, pierced him with his spear. The Jews intended that his legs should be broken, but this was prevented by the providence of God; yet in another way, more satisfactory proof of his death was obtained than would have been by the breaking of his legs. This was undoubtedly ordained so that there might be the fullest proof that he was truly dead; that it could not be claimed he had merely fainted and revived; and thus, that there could not be the least doubt of his resurrection to life.

With a spear. The common spear that soldiers used in war. There can be no doubt that such a stroke from the strong arm of a Roman soldier would have caused death, if he had not been already dead. It was, doubtless, to furnish this conclusive proof that he was actually dead, and that an atonement had thus been made for mankind, that John mentions this fact so particularly. Let the following circumstances be remembered, which show that death must have resulted from such a wound:

1. The Savior was elevated only a little from the ground, so as to be easily reached by a soldier's spear.
2. The wound must have been transversely upward, penetrating the body, as the soldier could not have stood directly under him.
3. It was probably made with a strong arm and with violence.
4. The spear of the Roman soldier was a lance that tapered very gently to a point and would penetrate easily.
5. The wound was comparatively a large wound. It was so large as to admit the hand (John 20:27). For a lance tapering so gently to make a wound wide enough to admit a hand, it must have been at least four or five inches deep and would certainly have caused death. If it is remembered that this blow was probably in the left side, the conclusion is inevitable that death would have been the consequence of such a blow. Establishing this fact was especially important in John's time, as the Gnostics denied the reality of Jesus' death, with many maintaining that he died in appearance only.

Pierced his side. Which side is not mentioned, nor can it be certainly known. The common opinion is that it was the left side. Carl Friedrich Gruner (Commentatio Anti-guavia Medica de Jesu Christi Morte, p. 30-36) has attempted to show that it must have been the left side. See Wiseman's Lectures, pages 161-162, and Kuinoel on John 19:34, where Gruner's arguments are fully stated. It is clear that the spear pierced to the region of the heart.

And forthwith came, etc. This was evidently a natural effect of piercing the side in this way. Such a flowing of blood and water makes it probable that the spear reached the heart, and if Jesus had not been dead before, this would have ended his life. The heart is surrounded by a membrane called the pericardium.

This membrane contains a serous matter or fluid resembling water, which prevents the surface of the heart from becoming dry from its continual motion (Webster). It was this membrane that was pierced and from which the water flowed. The point of the spear also reached one of the ventricles of the heart, and the blood, still warm, rushed out, either mixed with or followed by the water of the pericardium, so as to appear to John as blood and water flowing together.

This was a natural effect and would follow in any other case. Commentators have almost uniformly supposed that this was significant; for example, that the blood was an emblem of the Eucharist and the water of baptism, or that the blood denoted justification and the water sanctification. However, there is not the slightest evidence that this was the design.

It was strictly a natural result, adduced by John to establish one fact on which the whole of Christianity turns—that he was truly dead. On this depends the doctrine of the atonement, his resurrection, and all the prominent doctrines of religion. It was important to prove this fact, so that it could not be claimed that he had only suffered a syncope or fainted.

This John establishes. He shows that those who were sent to hasten his death believed that he had expired; that then a soldier inflicted a wound that would have terminated life if he had not already been dead; and that the infliction of this wound was followed by the fullest proof that he had truly expired. On this fact he dwells with the interest appropriate for a subject of such importance to the world, and thus laid the foundation for undoubted assurance that the Lord Jesus died for the sins of men.

(See 1 Peter 3:21 concerning water).