Deuteronomy 9:9

9:9 When I went up the mountain to receive the stone tablets, the tablets of the covenant that the Lord made with you, I remained there forty days and nights, eating and drinking nothing.

Deuteronomy 9:18

9:18 Then I again fell down before the Lord for forty days and nights; I ate and drank nothing because of all the sin you had committed, doing such evil before the Lord as to enrage him.