Yom Kippur, the Day of Atonement, is the holiest and most somber day of the Jewish year.
“The tenth day of this seventh month is the Day of Atonement. Hold a sacred assembly and deny yourselves, and present an offering made by fire to the Lord. Do no work on that day, because it is the Day of Atonement, when atonement is made for you before the Lord your God. Those who do not deny themselves on that day must be cut off from their people. … This is to be a lasting ordinance for the generations to come, wherever you live. It is a sabbath of rest for you and you must deny yourselves. From the evening of the ninth day of the month until the following evening you are to observe your sabbath.” (Leviticus 23:27-32)
The purpose of these commands was not the impassive, outward-only performance of ritual, but the restoration of intimate relationship between a holy God and His beloved, covenant people.
When God graciously instituted the New Covenant promised to Israel in Jeremiah 31:33, the sacrificial system was no longer needed. The singular, blood sacrifice of Messiah Yeshua accomplished atonement for all humankind. “He sacrificed for their sins once for all when He offered Himself.” (Hebrews 7:27)