{11} But one of the soldiers with a spear {d} pierced his side, and forthwith came there out blood and water.

(11) Christ, being dead upon the cross, witnesses by a double sign that he alone is the true satisfaction, and the true washing for the believers.

(d) This wound was a most manifest witness of the death of Christ: for the water that issued out by this wound shows us plainly that the weapon pierced the very skin that encompasses the heart, and this skin is the vessel that contains the water; and once that is wounded, the creature which is so pierced and stricken has no choice but to die.

People's New Testament

19:34 Pierced his side. Finding him lifeless, the soldiers did not break his legs, but to make sure of death thrust a spear into his side.

Came there out blood and water. The water, with clots of blood, can be accounted for only the previous rupture of the heart and the flow of blood into the pericardium, or outer sack of the heart, where it would separate very rapidly into water and clots of blood. Hence, it seems certain that the immediate physical cause of the death of Christ was rupture of the heart.

Wesley's Notes

19:34 Forthwith there came out blood and water - It was strange, seeing he was dead, that blood should come out; more strange, that water also; and most strange of all, that both should come out immediately, at one time, and yet distinctly. It was pure and true water, as well as pure and true blood. The asseveration of the beholder and testifier of it, shows both the truth and greatness of the miracle and mystery.

Jamieson-Fausset-Brown Bible Commentary

34. But one of the soldiers-to make assurance of the fact doubly sure.

with a spear pierced his side-making a wound deep and wide, as indeed is plain from Joh 20:27, 29. Had life still remained, it must have fled now.

and forthwith came thereout blood and water-"It is now well known that the effect of long-continued and intense agony is frequently to produce a secretion of a colorless lymph within the pericardium (the membrane enveloping the heart), amounting in many cases to a very considerable quantity" [Webster and Wilkinson].

Matthew Henry's Concise Commentary

19:31-37 A trial was made whether Jesus was dead. He died in less time than persons crucified commonly did. It showed that he had laid down his life of himself. The spear broke up the very fountains of life; no human body could survive such a wound. But its being so solemnly attested, shows there was something peculiar in it. The blood and water that flowed out, signified those two great benefits which all believers partake of through Christ, justification and sanctification; blood for atonement, water for purification. They both flow from the pierced side of our Redeemer. To Christ crucified we owe merit for our justification, and Spirit and grace for our sanctification. Let this silence the fears of weak Christians, and encourage their hopes; there came both water and blood out of Jesus' pierced side, both to justify and sanctify them. The Scripture was fulfilled, in Pilate's not allowing his legs to be broken, Ps 34:20. There was a type of this in the paschal lamb, Ex 12:46. May we ever look to Him, whom, by our sins, we have ignorantly and heedlessly pierced, nay, sometimes against convictions and mercies; and who shed from his wounded side both water and blood, that we might be justified and sanctified in his name.