Exodus 24:15-17

Young's Literal Translation

¹⁵ And Moses goeth up unto the mount, and the cloud covereth the mount;

¹⁶ and the honour of Jehovah doth tabernacle on mount Sinai, and the cloud covereth it six days, and He calleth unto Moses on the seventh day from the midst of the cloud.

¹⁷ And the appearance of the honour of Jehovah [is] as a consuming fire on the top of the mount, before the eyes of the sons of Israel;