The Enarrations, or Expositions, on the Psalms

^35. There is also in that sea somewhat which transcends all creatures, great and small. What is this? Let us hear the Psalm: “There is that Leviathan, whom You have formed to make sport of him.” There are creeping things innumerable, both small and great beasts; there shall the ships go, and shall not fear, not only the creeping things innumerable, and beasts both small and great, but not even the serpent which is there; “whom Thou,” he speaks unto God, “hast made to make sport of him.” This is a great mystery; and yet I am about to utter what ye already know. You know that a certain serpent is the enemy of the Church: you have not seen him with the eyes of the flesh, but you see him with the eyes of faith....