Exodus 14:20
19 The angel of God, who was going before the camp of Israel, moved and went behind them, and the pillar of cloud moved from before them and stood behind them. 20 It came between the Egyptian camp and the Israelite camp; it was a dark cloud and it lit up the night so that one camp did not come near the other the whole night. 21 Moses stretched out his hand toward the sea, and the Lord drove the sea apart by a strong east wind all that night, and he made the sea into dry land, and the water was divided.
Onkelos Exodus 14:20
19 And the angel of the Lord who went before the camp of Israel passed by and came behind them; and the column of the cloud passed from before them and abode behind them. 20 And it entered between the camp of the Mizraee and the camp of Israel; and was a cloud and darkness to the Mizraee, but to Israel it was a light all the night: and that came not near to this all the night. 21 And Mosheh stretched forth his hand over the sea; and the Lord drave the sea by a mighty east wind all the night, and caused the sea to be dry, and the waters were disparted;
Notes and References
"... Onkelos clarifies a very unclear biblical description of this event that reads: 'And there were cloud and darkness and it illuminated the night' ..."
Drazin, Israel, and Stanley M. Wagner Onkelos on the Torah, Exodus: Understanding the Bible Text (pp. 82-83) Gefen, 2006