Exodus 10:21 in the World English Bible
The LORD 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.”
Context
20 But the LORD hardened Pharaoh’s heart, so that he would not let the children of Israel go.
21 And the LORD said unto Moses, Stretch out thine hand toward heaven, that there may be darkness over the land of Egypt, even darkness which may be felt.
22 And Moses stretched forth his hand toward heaven; and there was a thick darkness in all the land of Egypt three days: