The similarities between Herman Melville's novel Moby Dick, and the story of Jonah in the Bible center around the whale, and the faith of the two protagonists.
In the story of Moby Dick, the major conflict revolves around Captain Ahab and his obsession to kill the white whale, Moby Dick, who maimed him the last time they confronted one another. Ahab is named after a wicked Biblical king in the Old Testament. Ahab is a Quaker—allegedly a man of God—and is supposed to be a pacifist (peacemaker), but has turned his back on his faith. He has lost sight of everything but killing the whale who he sees as the personification of evil. His unhealthy preoccupation with destroying the whale ultimately brings about the death of the entire crew, except for Ishmael.
In the story of Jonah, he, too, is a man of God. He has been called by God to go speak to the people of Nineveh. Jonah did not want to do so, so in essence, he too turned his back on God and boarded a boat to take him in the opposite direction. Soon a storm assaulted the boat, and Jonah, sure that he was the reason for the danger the ship was in, convinced the ship's crew to throw him overboard in order to save themselves. They did so, and Jonah was swallowed by a great fish (which we would refer to as a "whale.") When he repents, he visits Nineveh, and the people make peace with God and are saved.
Similarities are as follows: both are religious men; each has an experience with a whale; each man turns his back on his faith.
Differences are as follows: both men turn their back on God. Ahab never finds his way back to God and brings about the destruction of the majority of his crew. Jonah, on the other hand, saves the lives of the crew members on his ship and he turns himself around and fulfills God's purpose, saving the people of Nineveh.
While the whale brings about Ahab's death, it is the whale that saves Jonah from drowning.
Melville used many Biblical allusions in the classic tale of Ahab and the white whale Moby Dick.