Theophylact of Ohrid
Catena Aurea · Johannesevangelium 19
The Jews therefore, because it was the preparation, that the bodies should not remain upon the cross on the sabbath day, (for that sabbath day was an high day,) besought Pilate that their legs might be broken, and that they might be taken away. Then came the soldiers, and brake the legs of the first, and of the other which was crucified with him. But when they came to Jesus, and saw that he was dead already, they brake not his legs: But one of the soldiers with a spear pierced his side, and forthwith came there out blood and water. And he that saw it bare record, and his record is true: and he knoweth that he saith true, that ye might believe. For these things were done, that the Scripture should be fulfilled, A bone of him shall not be broken. And again another Scripture saith, They shall look on him whom they pierced. Besought Pilate that their legs might be broken.
Shame then upon them who mix not water with the wine in the holy mysteries: they seem as if they believed not that the water flowed from the side. Had blood flowed only, a man might have said that there was some life left in the body, and that that was why the blood flowed. But the water flowing is an irresistible miracle, and therefore the Evangelist adds, And he that saw it bare record.