Forty: Days by Moses
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Exodus 24:18
Moses entered the cloud as he went up on the mountain, and he remained on the mountain forty days and forty nights.
Exodus 34:28
So Moses was there with the LORD forty days and forty nights without eating bread or drinking water. He wrote on the tablets the words of the covenant—the Ten Commandments.
Deuteronomy 9:9, 25
When 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. / So I fell down before the LORD for forty days and forty nights, because the LORD had said He would destroy you.