Leviticus 23:26-32

And Jehovah spake unto Moses, saying, Howbeit on the tenth day of this seventh month is the day of atonement: it shall be a holy convocation unto you, and ye shall afflict your souls; and ye shall offer an offering made by fire unto Jehovah. And ye shall do no manner of work in that same day; for it is a day of atonement, to make atonement for you before Jehovah your God. For whatsoever soul it be that shall not be afflicted in that same day; he shall be cut off from his people. And whatsoever soul it be that doeth any manner of work in that same day, that soul will I destroy from among his people. Ye shall do no manner of work: it is a statute for ever throughout your generations in all your dwellings. It shall be unto you a sabbath of solemn rest, and ye shall afflict your souls: in the ninth day of the month at even, from even unto even, shall ye keep your sabbath.