Moses is described in the Bible as being on Mount Sinai for forty days and forty nights each time he went up there to receive the tablets of the Law (the Ten Commandments).

Quick answer

  • In Exodus 24, Moses goes up Mount Sinai and remains there 40 days and 40 nights while receiving the tablets and detailed instructions for Israel.
  • Later, after the golden calf incident and the breaking of the first tablets, Moses again goes back up the mountain for another 40 days and 40 nights during the covenant renewal.

So when people ask “how long was Moses on the mountain?”, the standard biblical answer is 40 days and 40 nights (with many scholars and teachers noting he did this twice, for a total of two such periods).

“Moses was on the mountain forty days and forty nights.” – Exodus 24:18 (seen across multiple Bible translations).

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