Deuteronomy 9:18-20

18Then I fell down before the LORD for forty days and forty nights, as I had done the first time. I did not eat bread or drink water because of all the sin you had committed in doing what was evil in the sight of the LORD and provoking Him to anger. 19For I was afraid1 of the anger and wrath that the LORD had directed against you, enough to destroy you. But the LORD listened to me this time as well.

20The LORD was angry enough with Aaron to destroy him, but at that time I also prayed for Aaron.