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.
There is but one thing that makes leviathan repulsive, his foul smell: which is so strong that if it penetrated thither, it would render Paradise itself an impossible abode.
The real purpose of leviathan is to be served up as a dainty to the pious in the world to come. The female was put into brine as soon as she was killed, to be preserved against the time when her flesh will be needed. The male is destined to offer a delectable sight to all beholders before he is consumed. When his last hour arrives, God will summon the angels to enter into combat with the monster. But no sooner will leviathan cast his glance at them than they will flee in fear and dismay from the field of battle. They will return to the charge with swords, but in vain, for his scales can turn back steel like straw. They will be equally unsuccessful when they attempt to kill him by throwing darts and slinging stones; such missiles will rebound without leaving the least impression on his body. Disheartened, the angels will give up the combat, and God will command leviathan and behemot to enter into a duel with each other. The issue will be that both will drop dead, behemot slaughtered by a blow of leviathan's fins, and leviathan killed by a lash of behemot's tail. From the skin of leviathan God will construct tents to shelter companies of the pious while they enjoy the dishes made of his flesh. The amount assigned to each of the pious will be in proportion to his deserts, and none will envy or begrudge the other his better share. What is left of leviathan's skin will be stretched out over Jerusalem as a canopy, and the light streaming from it will illumine the whole world, and what is left of his flesh after the pious have appeased their appetite, will be distributed among the rest of men, to carry on traffic therewith.
On the same day with the fishes, the birds were created, for these two kinds of animals are closely related to each other. Fish are fashioned out of water, and birds out of marshy ground saturated with water.
As leviathan is the king of fishes, so the ziz is appointed to rule over the birds. His name comes from the variety of tastes his flesh has; it tastes like this, zeh, and like that, zeh. The ziz is as monstrous of size as leviathan himself. His ankles rest on the earth, and his head reaches to the very sky.
It once happened that travellers on a vessel noticed a bird. As he stood in the water, it merely covered his feet, and his head knocked against the sky. The onlookers thought the water could not have any depth at that point, and they prepared to take a bath there. A heavenly voice warned them: "Alight not here! Once a carpenter's axe slipped from his hand at this spot, and it took it seven years to touch bottom." The bird the travellers saw was none other than the ziz. His wings are so huge that unfurled they darken the sun. They protect the earth against the storms of the south; without their aid the earth would not be able to resist the winds blowing thence. Once an egg of the ziz fell to the ground and broke. The fluid from it flooded sixty cities, and the shock crushed three hundred cedars. Fortunately such accidents do not occur frequently. As a rule the bird lets her eggs slide gently into her nest. This one mishap was due to the fact that the egg was rotten, and the bird cast it away carelessly. The ziz has another name, Renanin, because he is the celestial singer. On account of his relation to the heavenly regions he is also called Sekwi, the seer, and, besides, he is called "son of the nest," because his fledgling birds break away from the shell without being hatched by the mother bird; they spring directly from the nest, as it were. Like leviathan, so ziz is a delicacy to be served to the pious at the end of time, to compensate them for the privations which abstaining from the unclean fowls imposed upon them.