Deuteronomy 9:18-20

New Catholic Bible

¹⁸ Then I fell prostrate before the Lord for forty days and for forty nights.^[a] I did not eat food nor did I drink water on account of all the sins you had committed, doing what was so evil in the sight of the Lord that you provoked him to anger. ¹⁹ I feared the anger and the wrath of the Lord, for he was angry enough at you to destroy you. Yet, the Lord once again listened to me.

²⁰ The Lord was angry enough at Aaron to kill him, but I also prayed for Aaron at the same time.