Whenever the three days and three nights of Matthew 12:40 is brought up in a discussion with 6th day crucifixion folks, they frequently argue that it is a Jewish idiom for counting any part of a day as a whole day. I wonder if anyone has documentation that shows that the phrase x days and xnights was ever used in the first century or before when it absolutely didnt include at least parts of the x days and at least parts of the x nights?