Exodus 14:20-22

Amplified Bible

²⁰ So it came between the camp of Egypt and the camp of Israel. It was a cloud along with darkness [even by day to the Egyptians], but it gave light by night [to the Israelites]; so one [army] did not come near the other all night.

²¹ Then Moses stretched out his hand over the sea; and the Lord swept the sea back by a strong east wind all that night and turned the seabed into dry land, and the waters were divided. ²² The Israelites went into the middle of the sea on dry land, and the waters formed a wall to them on their right hand and on their left.