Deuteronomy 9:18-20

And I fell down before the LORD, as at the first, forty days and forty nights: I did neither eat bread, nor drink water, because of all your sins which ye sinned, in doing wickedly in the sight of the LORD, to provoke him to anger. For I was afraid of the anger and hot displeasure, wherewith the LORD was wroth against you to destroy you. But the LORD hearkened unto me at that time also. And the LORD was very angry with Aaron to have destroyed him: and I prayed for Aaron also the same time.