Three Days and Three Nights?

Was Yeshua in the grave for a literal 72 hours, three full days and three full nights? Or was that just an idiom that could mean a shorter length of time?

For more on a pro-Torah perspective on Passover and Yeshua (aka Jesus):

http://www.americantorah.com/?s=passover
https://soilfromstone.blogspot.com/search?q=passover