Yom Kippur is closely related to Rosh Hashanah, occurring just nine days later. It is also known as the Day of Atonement and it is the holiest day of the year for the Jewish people. This day is filled with fasting and prayer, with most of the day spent in synagogue services.
27 Also on the tenth day of this seventh month there shall be a day of atonement: it shall be a holy convocation to you; and you shall afflict your souls, and offer an offering made by fire to the LORD. 28 And you 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.
The importance of atonement and repentance at this time is regarded as critical since on this day the books which will determine the fate of all individuals for the next year will be sealed. It is also believed that Rosh Hashanah is the anniversary of Adam’s sin and repentance and atonement for it was completed on Yom Kippur.
23 Therefore if you bring your gift to the altar, and remember that your brother has anything against you; 24 Leave there your gift before the altar, and go your way; first be reconciled to your brother, and then come and offer your gift.
Between Rosh Hashanah and Yom Kippur, it is common to seek reconciliation with persons you may have wronged during the course of the previous year. To atone for sins against another person, you must first seek reconciliation with that person, righting the wrongs you committed against them if possible. With this done, the pathway is then cleared for atonement to be made before the LORD.