Psalm 81:3

““Sound the trumpet” (ver. 3).” — the author cites it

“…priests sounding and urging its observance; as the holy Psalmist commanded, saying, ‘Blow with the trumpet in the new moon, on the [solemn] day of your feast.’” — editor's note: Ps. lxxxi. 3, cf. Num. x. 8.

“And the prophet cries; ‘Keep thy feasts, O Judah.’” — editor's note: Numb. ix. 2; Ps. lxxxi. 3; Nah. i. 15

“We read also: “Blow up the trumpet at the beginning of the month [the new moon]”; and again elsewhere: “Praise Him with the sound of the trumpet.”” — editor's note: Ps. lxxxi. [lxxx.] 3.