<b>And Moses stretched forth his hand toward heaven; and there was a thick darkness in all the land of Egypt three days (Exod. 10:22).</b> Our sages maintained: There were seven days of darkness. During the first three days, a person who was sitting could stand if he wished to do so, and so too one who was standing could sit down. During the final three days, those who were sitting were unable to stand, those who were standing were unable to sit, and those who were reclining were unable to arise. Whence do we know this? From the fact that it is said; <i>And they saw not one another for three days</i> (ibid., v. 23). Hence for three days they could not change their positions, and for three days they could not arise from their places.
What was the seventh day like? <i>And there was the cloud and the darkness here, yet gave it light</i> (Exod. 14:20). This light resembled the light experienced at the sea. Similarly in Egypt the cloud gave light to the Israelites but darkness to the Egyptians, as it is said: <i>They saw not</i>.
<i>All the children of Israel had light</i> (ibid. 10:23). This implies that everything was illumined and disclosed to the Israelites—all the silver and gold utensils, the garments and the valuables of Egypt. Even the things that were in their boxes, barrels, and treasure chests were visible to them. And whatever the Israelites requested of them, they surrendered voluntarily, for the Israelites would say to them: “Behold, in that certain place you have such a utensil.” Hence, <i>And there was a thick darkness</i>.