Gregory the Dialogist

Hast thou entered into the depth of the sea, and hast thou walked in the lowest parts of the abyss? As if He said, As I, Who not only sought the sea, that is this world, by assuming the flesh and soul of a man, but also descended by that flesh voluntarily subjected to death, to the bottom of the pit, as if to the depths of the sea. For if the 'sea' must be understood to mean the world after the manner of Scripture language, nothing hinders the 'depths of the sea' from meaning the bars of the pit. …

Morals on the Book of Job, Book XXIX ↗

Thomas Aquinas

After these premises about the earthquake and its effects, he proceeds to the disposition of the middle element, i.e., the sea, where man believes there are marvelous things hidden. First, those things which are in the depths of the sea, for example, the habitats of the fish living in the sea, and as to this he says, "Have you entered into the depths of the sea," so that you know the animals which are hidden there? …

Commentary on Job ↗