Numbers 29:1, 12, 35

And in the seventh month, on the first day of the month, ye shall have an holy convocation; ye shall do no servile work: it is a day of blowing the trumpets unto you.

And on the fifteenth day of the seventh month ye shall have an holy convocation; ye shall do no servile work, and ye shall keep a feast unto the LORD seven days

On the eighth day ye shall have a solemn assembly: ye shall do no servile work therein