Exodus 24:12-15

Then the LORD said to Moses, “Come up to Me on the mountain and be there; and I will give you tablets of stone, and the law and commandments which I have written, that you may teach them.” So Moses arose with his assistant Joshua, and Moses went up to the mountain of God. And he said to the elders, “Wait here for us until we come back to you. Indeed, Aaron and Hur are with you. If any man has a difficulty, let him go to them.” Then Moses went up into the mountain, and a cloud covered the mountain.