Leviticus 23:15

The Festival of Weeks

23:15 “‘You must count for yourselves seven weeks from the day after the Sabbath, from the day you bring the wave offering sheaf; they must be complete weeks.

Leviticus 23:28

23:28 You must not do any work on this particular day, because it is a day of atonement to make atonement for yourselves before the Lord your God.