Exodus 40:34-38 ESV
Then the cloud covered the tent of meeting, and the glory of the LORD filled the tabernacle. And Moses was not able to enter the tent of meeting because the cloud settled on it, and the glory of the LORD filled the tabernacle. Throughout all their journeys, whenever the cloud was taken up from over the tabernacle, the people of Israel would set out. But if the cloud was not taken up, then they did not set out till the day that it was taken up. For the cloud of the LORD was on the tabernacle by day, and fire was in it by night, in the sight of all the house of Israel throughout all their journeys.
ESV: English Standard Version 2016