The Jews came up with it first.
40 is the biblical number for God’s judgement. Noah’s flood rained for 40 days and nights—and the world was destroyed. The Hebrews wandered 40 years in the Wilderness,with an entire generation dying.... before going into the Promised land. Jesus fasted and was tempted for 40 days.
40 is a very eerie number.
40 days,yup.