Exodus 40:34-38

Then the cloud covered the tent of meeting, and the glory of the LORD filled the tabernacle. Moses was not able to enter the tent of meeting because the cloud had 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 sons of Israel would set out; but if the cloud was not taken up, then they did not set out until the day when it was taken up. For throughout all their journeys, the cloud of the LORD was on the tabernacle by day, and there was fire in it by night, in the sight of all the house of Israel.