Deuteronomy 9:15
So I turned and came down from the mount, and the mount burned with fire: and the two tables of the covenant were in my two hands. So I turned and came down from the mount, and the mount burned with fire: and the two tables of the covenant were in my two hands.
Moses in coming down from the burning mount with the two tables of the covenant in his hands was reminding Israel of their own history of rebellion. For that rebellion the Lord had repeatedly purposed to destroy them. Yet Moses had interceded for them so earnestly that God had graciously spared them.
He joined that mercy with the great acts and miracles done to Pharaoh and to all the land of Egypt. Those acts their own eyes had seen. On that ground he charged them to keep all the commandments, so that they would be strong and go in and possess the land they were going to possess.