Exodus 14:19-20

19 Then the angel of the Almighty Ones, who had been traveling in front of Yasrael's army, withdrew and went behind them.   The pillar of cloud also moved from in front and stood behind them,

20 coming between the armies of Egypt and Yasrael.   Throughout the night the cloud brought darkness to the one side and light to the other side; so neither went near the other all night long.