On the fifth day of creation God took fire and water, and out of these two elements He made the fishes of the sea. The animals in the water are much more numerous than those on land. For every species on land, excepting only the weasel, there is a corresponding species in the water, and, besides, there are many found only in the water.
The ruler over the sea-animals is leviathan. With all the other fishes he was made on the fifth day. Originally he was created male and female like all the other animals. But when it appeared that a pair of these monsters might annihilate the whole earth with their united strength, God killed the female. So enormous is leviathan that to quench his thirst he needs all the water that flows from the Jordan into the sea. His food consists of the fish which go between his jaws of their own accord. When he is hungry, a hot breath blows from his nostrils, and it makes the waters of the great sea seething hot. Formidable though behemot, the other monster, is, he feels insecure until he is certain that leviathan has satisfied his thirst. The only thing that can keep him in check is the stickleback, a little fish which was created for the purpose, and of which he stands in great awe. But leviathan is more than merely large and strong; he is wonderfully made besides. His fins radiate brilliant light, the very sun is obscured by it, and also his eyes shed such splendor that frequently the sea is illuminated suddenly by it. No wonder that this marvellous beast is the plaything of God, in whom He takes His pastime.