Leviticus 25:9

25:9 You must sound loud horn blasts – in the seventh month, on the tenth day of the month, on the Day of Atonement – you must sound the horn in your entire land.

sn On the “loud horn blasts” see the note on Lev 23:24, but unlike the language there, the Hebrew term for “horn” (שׁוֹפָר, shofar) actually appears here in this verse (twice).