'Day of Atonement' in the Bible

Also, on the tenth of this seventh month, this is a day of atonement. It shall be a holy convocation to you. And you shall afflict your souls and offer a fire offering to Jehovah.

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

Then you shall cause the trumpet of the jubilee to sound on the tenth of the seventh month; in the day of atonement, the trumpet shall sound throughout all your land.