Yom Kippur falls on the tenth of Tishrei, the date this rule records, closing the Ten Days of Repentance that open with Rosh Hashanah. The Torah's own language in Leviticus sixteen and twenty three is notably restrained, commanding that the people afflict their souls on this day and do no work, without spelling out fasting explicitly, a gap rabbinic tradition later closed by reading the affliction as a twenty five hour abstention from food, drink, washing, anointing, leather footwear and marital relations, the fullest fast in the Hebrew calendar.
The day's theological framing as the culmination of atonement, closing what tradition describes as the Book of Life opened on Rosh Hashanah, developed alongside the practice rather than preceding it in the biblical text. The Temple period observance described in Leviticus sixteen centered on a specific priestly rite, including the scapegoat sent into the wilderness carrying the community's sins, a practice that ended with the Temple's destruction in 70 CE and was replaced by the prayer centered observance kept today, closing with the Neilah service at sunset, a final appeal made, in traditional understanding, in the last moments before the day's judgment is sealed.