'Day of Atonement' in the Bible

Howbeit on the tenth day of this seventh month is the day of atonement: it shall be a holy convocation unto you, and ye shall afflict your souls; and ye shall offer an offering made by fire unto Jehovah.

And ye shall do no manner of work in that same day; for it is a day of atonement, to make atonement for you before Jehovah your God.

Then shalt thou send abroad the loud trumpet on the tenth day of the seventh month; in the day of atonement shall ye send abroad the trumpet throughout all your land.