Exodus 33:9-11

As he went into the tent, the pillar of cloud would come down and hover at its entrance while the LORD spoke with Moses. When the people saw the cloud standing at the entrance of the tent, they would stand and bow down in front of their own tents. Inside the Tent of Meeting, the LORD would speak to Moses face to face, as one speaks to a friend. Afterward Moses would return to the camp, but the young man who assisted him, Joshua son of Nun, would remain behind in the Tent of Meeting.