Tractates on the Gospel of John

¹¹ He endured death, then; but death He hanged on the cross, and mortal men are delivered from death. The Lord calls to mind a great matter, which was done in a figure with them of old: “And as Moses,” says He, “lifted up the serpent in the wilderness, so must the Son of man be lifted up; that every one who believes in Him may not perish, but have everlasting life.” A great mystery is here, as they who read know. Again, let them hear, as well they who have not read as they who have forgotten what perhaps they had heard or read.

The people Israel were fallen helplessly in the wilderness by the bite of serpents; they suffered a great calamity by many deaths: for it was the stroke of God correcting and scourging them that He might instruct them. In this was shown a great mystery, the figure of a thing to come: the Lord Himself testifies in this passage, so that no man can give another interpretation than that which the truth indicates concerning itself. Now Moses was ordered by the Lord to make a brazen serpent, and to raise it on a pole in the wilderness, and to admonish the people Israel, that, when any had been bitten by a serpent, he should look to that serpent raised up on the pole.

This was done: men were bitten; they looked and were healed. What are the biting serpents? Sins, from the mortality of the flesh. What is the serpent lifted up? The Lord's death on the cross. For as death came by the serpent, it was figured by the image of a serpent. The serpent's bite was deadly, the Lord's death is life-giving. A serpent is gazed on that the serpent may have no power. What is this? A death is gazed on, that death may have no power. But whose death? The death of life: if it may be said, the death of life; ay, for it may be said, but said wonderfully.

But should it not be spoken, seeing it was a thing to be done? Shall I hesitate to utter that which the Lord has deigned to do for me? Is not Christ the life? And yet Christ hung on the cross. Is not Christ life? And yet Christ was dead. But in Christ's death, death died. Life dead slew death; the fullness of life swallowed up death; death was absorbed in the body of Christ. So also shall we say in the resurrection, when now triumphant we shall sing, “Where, O death, is your contest?

Where, O death, is your sting?” Meanwhile brethren, that we may be healed from sin, let us now gaze on Christ crucified; for “as Moses,” says He, “lifted up the serpent in the wilderness, so must the Son of man be lifted up; that whosoever believes in Him may not perish, but have everlasting life.” Just as they who looked on that serpent perished not by the serpent's bites, so they who look in faith on Christ's death are healed from the bites of sins. But those were healed from death to temporal life; while here He says, “that they may have everlasting life.” Now there is this difference between the figurative image and the real thing: the figure procured temporal life; the reality, of which that was the figure, procures eternal life.