Leviticus 25:9

“On exactly the tenth day of this seventh month is the day of atonement; it shall be a holy convocation for you, and you shall humble your souls and bring an offering by fire near to Yahweh.

“Also seven priests shall carry seven trumpets of rams’ horns before the ark; then on the seventh day you shall march around the city seven times, and the priests shall blow the trumpets.

And it will be in that day, that a great trumpet will be blown, and those who were perishing in the land of Assyria and who were banished in the land of Egypt will come and worship Yahweh in the holy mountain at Jerusalem.