The Door in the Side of the Ark and the Wound in the Side of Christ
Old Testament: Genesis 6:16
Thou shalt make a window in the ark, and in a cubit shalt thou finish the top of it: and the door of the ark thou shalt set in the side: with lower, middle chambers, and third stories shalt thou make it.
Old Testament, also: Genesis 7:16
And they that went in, went in male and female of all flesh, as God had commanded him: and the Lord shut him in on the outside.
New Testament: John 19:34
But one of the soldiers with a spear opened his side, and immediately there came out blood and water.
The connection
Genesis gives the ark's door a location and nothing else. Among the cubits and the storeys and the pitch there is one clause: "the door of the ark thou shalt set in the side" (Genesis 6:16). It is a construction note. It is also the only way in. Everything that comes through the flood alive comes through that single opening in the flank of the vessel, and there is no other entrance anywhere in the design. Augustine reads that clause as a prophecy of where the way in would be, and he says so twice. In the City of God the door "certainly signified the wound which was made when the side of the Crucified was pierced with the spear; for by this those who come to Him enter; for thence flowed the sacraments by which those who believe are initiated" (Book XV, 26). In Against Faustus he puts it more shortly: "That the entrance is on the side; as no man enters the Church except by the sacrament of the remission of sins which flowed from Christ’s opened side" (Book XII, 16). The ark is the thing that carries a household through the water that kills everything else, and the door into it is cut in the side, so when the soldier's spear "opened his side" (John 19:34) the opening is not only a wound. It is the way aboard. Notice what Augustine holds together in one sentence: by this men enter, and from this the sacraments flow. The wound works in both directions at once, and the corpus reads each of them separately. At the struck rock the side is a source, struck so that something comes out of it, blood and water, and it does not stop. Here the side is a door, opened so that someone can go in through it. One opening, made by one spear, doing what no ordinary wound and no ordinary door does. Genesis then adds a detail that is easy to read past. When everything is aboard, "the Lord shut him in on the outside" (Genesis 7:16). Noe does not close the door behind himself. The door is opened by another and shut by another, and the safety of everyone inside depends on a hand they cannot see and cannot reach. That is the whole difference between a shelter a man builds and a shelter a man is put into. The last word about that door belongs to the Risen Christ, who opens it once more for one man who would not believe: "bring hither thy hand, and put it into my side" (John 20:27).
Moral sense
The way into safety is through a wound rather than around it, which is why the instinct to approach God by way of one's better parts gets the direction wrong; the opening is at the place of injury, and it was made from the outside by someone else.
Anagogical sense
The door of the ark was shut by the Lord and not by the passengers, and the shutting is as much mercy as the opening, since a door that anyone inside could work would be a door the flood could reach; what is finally sealed is sealed by the same hand that opened it.
The Fathers
St Augustine makes this reading twice. City of God, Book XV, 26: the ark "having a door made in the side of it certainly signified the wound which was made when the side of the Crucified was pierced with the spear; for by this those who come to Him enter; for thence flowed the sacraments by which those who believe are initiated." Against Faustus the Manichaean, Book XII, 16: "That the entrance is on the side; as no man enters the Church except by the sacrament of the remission of sins which flowed from Christ’s opened side." At Against Faustus XII, 39 he returns to it a third time, saying Philo, reading the door without Christ, "knew not the door and could not understand the symbol." Both passages were read against the printed text rather than reported from memory.
Warrant
Augustine draws this directly and repeatedly, in the City of God at XV, 26 and in Against Faustus at XII, 16 and again at XII, 39, and the sentences are quoted rather than summarised. The tier is patristic and not scriptural because John 19:34 names neither Genesis 6:16 nor the ark. A second Father was looked for and not found on this particular point: Origen, Chrysostom and Ambrose all read the pierced side as the birth of the Church, which is the reading behind Catechism 766, but the further step of identifying that wound with the door Genesis puts in the ark's flank appears to be Augustine's own, which is why he is quoted twice here rather than joined by others. Checked in the Greek, and the two side words differ: the Septuagint of Genesis 6:16 sets the door ek plagion, and John 19:34 has pleura, so nothing lexical carries the link and it stands on Augustine alone. One thing the Greek does hold, which belongs to another entry: the Septuagint calls Noe's vessel kibotos and calls the ark of the covenant kibotos too, one word where the Hebrew has two unrelated ones, tebah and aron. St John Chrysostom, Homily 85 on John, says of the water and blood from the side that "by means of these two together the Church consisteth," and adds, "Hence the Mysteries take their beginning; that when thou approachest to that awful cup, thou mayest so approach, as drinking from the very side," which answers to the second half of Augustine's sentence, though he says nothing of the ark or its door.
Catechism of the Catholic Church, paragraph 766.
