Canst thou draw out leviathan with an hook? or his tongue with a cord which thou lettest down? Job 41:1
In that day the LORD with his sore and great and strong sword shall punish leviathan the piercing serpent, even leviathan that crooked serpent; and he shall slay the dragon that is in the sea. Isaiah 27:1
Some Christians believe that Leviathan was a dragon or dinosaur (probably a Plesiosaurus), other sources speculate that it was a crocodile or a whale. In Moby Dick, the narrator Ishmael often uses the word leviathan to refer to whales.