What Does Exodus 14:20 Mean?

Coming between the host of Egypt and the host of Israel. And there was the cloud and the darkness. And it lit up the night without one coming near the other all night. The cloud that interposes between the two armies has a double quality: darkness toward Egypt, light toward Israel: the same paradox as the ninth plague (Exodus 10:21-23) when darkness covered Egypt while Israel had light in their dwellings.

The boundary between judgment and protection is the divine presence itself: the same cloud that provides protective light to Israel provides impenetrable darkness to Egypt. YHWH's presence is experienced oppositely by those under judgment and those under protection.

"And it lit up the night" (Hebrew: vayair et halayla, it gave light to the night), the cloud/fire pillar that lights Israel's path through the sea bed at night, is the miraculous illumination of the crossing. The sea crossing narrative specifies that it happens at night (verse 20, verse 21's east wind works through the night, verse 27 mentions morning), meaning Israel walks through the sea in divinely provided light while Egypt is held in darkness. The same dark cloud that blinds the Egyptian pursuit illuminates the Israelite passage.

"All night" (kol halayla) is the duration of the separation: the entire night passes without Egyptian contact with Israel. The night-long cloud-barrier gives Israel the time to cross the sea bed completely before Egypt is released to pursue. The divine time-management of the sea crossing is as precise as the Passover's midnight timing: YHWH structures the sequence (cloud barrier, night transit, morning pursuit, morning sea-closing) so that Israel is entirely across when Pharaoh's army enters.