1 Kings 8:9-11

9Nothing was in the ark except the two tablets of stone which Moses put there at Horeb, when the Lord made a covenant with the children of Israel, when they came out of the land of Egypt.

10And it came to pass, when the priests came out of the holy place, that the cloud filled the house of the Lord,

11so that the priests could not continue ministering because of the cloud; for the glory of the Lord filled the house of the Lord.