Last time we heard about the plague of hail that God sent on Egypt, and at the end of that story Pharaoh seemed to relent... however, he quickly changed his mind. God showed his power with two more plagues on the Egyptians, but still Pharaoh refused to let the people go.
So God explained to Moses his plan for the tenth and final plague. This time there would be no distinction between Egyptians and Israelites, the only way to be safe was to listen very carefully God's instructions...
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