Deuteronomy 9:9-11

9When I went up on the mountain to receive the tablets of stone, the tablets of the covenant that the LORD made with you, I stayed on the mountain forty days and forty nights. I ate no bread and drank no water.

10Then the LORD gave me the two stone tablets, inscribed by the finger of God with the exact words that the LORD spoke to you out of the fire on the mountain on the day of the assembly. 11And at the end of forty days and forty nights, the LORD gave me the two stone tablets, the tablets of the covenant.