The Day of Atonement was a festival to be celebrated by the Hebrews and Israelites, mandated by the biblical books of Leviticus and Numbers (both found in the Law). This day designated a special sabbath rest and was to be celebrated on the tenth day of the seventh month of the Hebrew calendar; ten days after the Feast of Trumpets. On this day the High Priest of the Levitical Priesthood would make several special offerings to serve as an annual atonement for the Israelite's sins.