When Israel came out of Egypt and stood at the shore of the Reed Sea, Samael — the angel who serves as heavenly prosecutor — rose up to accuse them.
"Lord of the Universe," Samael said, "these people have been worshipping idols in Egypt for generations. They are no better than the Egyptians pursuing them. And now You are going to split the sea for them? On what merit?"
The accusation had teeth. Israel had sunk low in Egypt. Heaven was silent for a dangerous moment.
What did the Holy One — blessed be He — do? He reached for a distraction.
Among Pharaoh's senior counselors was a man named Job, of whom Scripture itself says, "That man was perfect and upright" (Job 1:1). God took Job and handed him over to Samael. "Behold," He said, "he is in thy hand. Do with him as thou pleasest."
Samael, suddenly presented with a righteous man he could test and torment, turned his whole attention away from Israel and onto Job. While the accuser was busy with Job's sores and losses and debates, God said to Moses, "Speak to the children of Israel that they go forward" (Exodus 14:15). The sea parted. The people crossed.
Afterward, God returned and rescued Job from Samael's grip (Shemot Rabbah 21).
The story is jarring, and the rabbis meant it to be. In their telling, Job's suffering was not meaningless; it was the cost of Israel's salvation at the sea. And Ha-Satan, the Accuser, is not God's rival. He is God's prosecutor — and when the Judge wants him occupied, He gives him another case.