One of the soldiers with a spear opened his side, and immediately there came out blood and water. –John xix. 34.
1. The gospel deliberately says opened and not wounded, because through Our Lord’s side there was opened to us the gate of eternal life. After these things I looked, and behold a gate was opened in heaven (Apoc. iv. 1). This is the door opened in the ark, through which enter the animals who will not perish in the flood.
2. But this door is the cause of our salvation. Immediately there came forth blood and water, a thing truly miraculous, that, from a dead body, in which the blood congeals, blood should come forth.
This was done to show that by the Passion of Christ we receive a full absolution, an absolution from every sin and every stain. We receive this absolution from sin through that blood which is the price of our redemption. You were not redeemed with corruptible things as gold or silver, from your vain conversation with the tradition of your fathers; but with the precious blood of Christ, as of a lamb unspotted and undefiled (i Pet. i. 18).
We were absolved from every stain by the water, which is the laver of our redemption. In the prophet Ezechiel it is said, I will pour upon you clean water, and you shall be cleaned from all your filthiness (Ezech. xxxvi. 28), and in Zacharias, There shall be a fountain open to the house of David and to the inhabitants of Jerusalem for the washing of the sinner and the unclean woman (Zach. xiii. 1).
And so these two things may be thought of in relation to two of the sacraments, the water to baptism and the blood to the Holy Eucharist. Or both may be referred to the Holy Eucharist since, in the Mass, water is mixed with the wine. Although the water is not of the substance of the sacrament.
Again, as from the side of Christ asleep in death on the cross there flowed that blood and water in which the Church is consecrated, so from the side of the sleeping Adam was formed the first woman, who herself foreshadowed the Church. (In John xix.)