Deuteronomy 9:18

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.

I fell down before the Lord. The sudden and painful reaction which this scene of pagan revelry produced on the mind of the pious and patriotic leader can be more easily imagined than described. Great and public sins call for seasons of extraordinary humiliation; and in his deep affliction for the awful apostasy, he seems to have held a miraculous fast as long as before. These 40 days are not mentioned in the book of Exodus.