Exodus 10
21 Ref Yahweh said to Moses, "Stretch out your hand toward the sky, that there may be darkness over the land of Egypt, even darkness which may be felt."
22 Ref Moses stretched forth his hand toward the sky, and there was a thick darkness in all the land of Egypt three days.
23 Ref They didn't see one another, neither did anyone rise from his place for three days; but all the children of Israel had light in their dwellings.