The shofar is mentioned frequently in the Hebrew Bible, from Exodus to Zechariah, and throughout the Talmud and later rabbinic literature. It was the voice of a shofar, "exceeding loud," issuing from the thick cloud on Mount Sinai that made all the Israelites tremble in awe (Exodus 19, 20).
The shofar is prescribed for the announcement of the New Moon and solemn feasts (Num. x. 10; Ps. lxxxi. 4), as also for proclaiming the year of release (Lev. 25. 9). The first day of the seventh month (Tishri) is termed "a memorial of blowing" (Lev. 23. 24), or "a day of blowing" (Num. xxix. 1), the shofar; the modern use of the instrument survives especially in this connection. In earlier days it was employed also in other religious ceremonials, as processions (II Sam. 5. 15; I Chron. 15. 28), or in the orchestra as an accompaniment to the song of praise (Ps. 98. 6; comp. ib. xlvii. 5). More frequently it was used as the signal-horn of war, like the silver trumpets mentioned in Num. 10. 9 (see Josh. 6. 4; Judges 3. 27; 7. 16, 20; I Sam. 8. 3).
The Torah describes the first day of the seventh month (1st of Tishri = Rosh ha-Shanah) as a zikron teruah (memorial of blowing; Lev. xxiii) and as a yom teru'ah (day of blowing; Num. 29). This was interpreted by the Jewish sages as referring to the sounding the shofar.
The shofar in the Temple in Jerusalem was generally associated with the trumpet; and both instruments were used together on various occasions. On New-Year's Day the principal ceremony was conducted with the shofar, which instrument was placed in the center with a trumpet on either side; it was the horn of a wild goat and straight in shape, being ornamented with gold at the mouthpiece. On fast-days the principal ceremony was conducted with the trumpets in the center and with a shofar on either side. On those occasions the shofarot were rams' horns curved in shape and ornamented with silver at the mouthpieces. On Yom Kippur of the jubilee year the ceremony was performed with the shofar as on New-Year's Day.
The shofar was blown in the times of Joshua to help him capture Jericho. As they surrounded the walls the shofar was blown and the Jews were able to capture the city. The shofar was commonly taken out to war so the troops would know when a battle would begin. The person who would blow the shofar would call out to the troops from atop a hill. All of the troops were able to hear the call of the shofar from their position because of its distinct noise.
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