Leviticus 23:41
And ye shall keep it a feast unto the LORD seven days in the year. It shall be a statute for ever in your generations: ye shall celebrate it in the seventh month.
And ye shall keep it a feast unto the Lord seven days in the year,.... Every year it was to be kept for the space of seven days, beginning on the fifteenth and ending on the twenty second of the month Tisri or September;
It shall be a statute for ever in your generations; until the Messiah should come and tabernacle among men, the substance of this shadow, on whose coming it was to flee away:
ye shall celebrate it in the seventh month; which is repeated for the confirmation of it, and that no mistake might be made.