Splitting the Sea

The oldest layer of the exodus story has the Egyptian people, panicked by the plague of darkness, force the Israelites out under the king of Egypt’s nose. The story is later revised to credit the exodus to God's smiting the firstborn sons, and then drowning Pharaoh and his army in the sea. The final, Priestly editor added his signature theological innovation: God forces Pharaoh to give chase by hardening his heart.