Exodus 13:21

21And athe Lord went before them by day in a pillar of cloud to lead them along the way, and by night in a pillar of fire to give them light, that they might travel by day and by night.

Exodus 24:16

16 bThe glory of the Lord dwelt on Mount Sinai, and the cloud covered it six days. And on the seventh day he called to Moses out of the midst of the cloud.
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