Perhaps this day of sorrow cannot be strictly termed a feast day. But yet as being on the Sabbath, that sacred day lost not its name. Is not the LORD JESUS typically set forth here also, who in the days of his flesh offered up strong crying and tears. Hebrews 5:7-9. This was he, of whom Daniel spake, Daniel 9:24. And this was he, whom Paul describes, as having by himself purged our sins. Hebrews 1:3. Blessed LORD! as thou art exalted as a prince and a Saviour, to give to Israel repentance and remission of sins, give to me those ascension-gifts; that I may so look unto thee in every day's atonement of thy blood, as to mourn for thee. Zechariah 12:10.
Leviticus 23:26-32
26 And the LORD spake unto Moses, saying,
27 Also on the tenth day of this seventh month there shall be a day of atonement: it shall be an holy convocation unto you; and ye shall afflict your souls, and offer an offering made by fire unto the LORD.
28 And ye shall do no work in that same day: for it is a day of atonement, to make an atonement for you before the LORD your God.
29 For whatsoever soul it be that shall not be afflicted in that same day, he shall be cut off from among his people.
30 And whatsoever soul it be that doeth any work in that same day, the same soul will I destroy from among his people.
31 Ye shall do no manner of work: it shall be a statute for ever throughout your generations in all your dwellings.
32 It shall be unto you a sabbath of rest, and ye shall afflict your souls: in the ninth day of the month at even, from even unto even, shall ye celebrateb your sabbath.