The shofar is mentioned frequently in the Hebrew Bible, the Talmud and rabbinic literature. The blast of a shofar emanating from the thick cloud on Mount Sinai made the Israelites tremble in awe (Exodus 19, 20).
The shofar was used in biblical times to announce the New Moon, holidays (Num. x. 10; Ps. lxxxi. 4), and the Jubilee year (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. It was also employed in processions (II Sam. 6. 15; I Chron. 15. 28), as a musical accompaniment (Ps. 98. 6; comp. ib. xlvii. 5) and to signify the start of a war (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.
In the Temple in Jerusalem, the shofar was sometimes used together with the trumpet. 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. Rosh Hoshana is the Jewish New Year. A ceremonial horn, called a “shofar” is blown, reminding Jews that God is king. A feast with symbolic food is eaten on Rosh Hashana, and the next ten days are spent in repentance. Rosh hashana ends on Yom Kippur. Yom Kippur is a day of judgment, during which prayers are made asking for forgiveness.
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.
The shofar is primarily associated with Rosh ha-Shanah. Indeed, Rosh Hashanah is called "Yom T’ruah" (the day of the shofar blast). In the Mishnah (book of early rabbinic laws derived from the Torah), a discussion centers on the centrality of the shofar in the time before the destruction of the second temple (70 AD). Indeed, the shofar was the center of the ceremony, with two silver trumpets playing a lesser role. On other solemn holidays, fasts, and new moon celebrations, two silver trumpets were featured, with one shofar playing a lesser role. The shofar is also associated with the jubilee year in which, every fifty years, Jewish law provided for the release of all slaves, land, and debts. The sound of the shofar on Rosh ha-Shanah announced the jubilee year, and the sound of the shofar on Yom Kippur proclaimed the actual release of financial encumbrances.
The halakha (Jewish law) rules that the shofar may not be sounded on the Sabbath due to the potential that the ba’al tekiyah (shofar sounder) may inadvertently carry it which is in a class of forbidden Sabbath work (RH 29b) the historical explanation is that in ancient Israel, the shofar was sounded on the Shabbat in the temple located in Jerusalem. After the temple’s destruction, the sounding of the shofar on the Sabbath was restricted to the place where the great Sanhedrin (Jewish legislature and court from 400 BCE to 100 C.E.) was located. However, when the Sanhedrin ceased to exist, the sounding of the shofar on the Sabbath was discontinued (Kieval, The High Holy Days, p. 114).
The shofar says, "Wake up from your (moral) sleep. You are asleep. Get up from your slumber. You are in a deep sleep. Search for your behavior. Become the best person you can. Remember God, the One Who created you." Mishneh Torah, Laws of Repentance 3:4.
See Arthur l. Finkle, Shofar Sounders Reference Manual, LA: Torah Aura, 1993
According to the Talmud, a shofar may be made from the horn of any animal except that of a cow or calf (Rosh Hashanah, 26a), although a ram is preferable. (Mishnah Berurah 586:1). There is no requirement for ritual slaughter (shechitah), and theoretically, the horn can come from a non-kosher animal based on the principle of mutar beficha (the material is acceptable for putting in the mouth). Moreover, since the mitzvah is hearing the shofar, not eating it, using the horn of a neveylah or a non-kosher animal falls into the category of tashmishe mitzvah (MB 586:16 (8) Since unkosher substances unfit for human consumption are not food (Avot 67b), it is permissible to use animal hair, anointing oil and incense produced from animal secretions and dyes of crimson, which are made from mollusks (Megillah 26b).
To cap this issue, a recent article appeared in the Journal of Halacha, Number LIII, and Contemporary Society, Rabbi Ari Z, Zivotofsky, Yemenite Shofar: Ideal for the Mitzvah?, Cleveland, OH: Rabbi Jacob Joseph School R. Ari Z, Zivotofsky, 2007 The Elef Hamagan (586:5) delineates the order of preference: 1) curved ram; 2) curved other sheep; 3) curved other animal; 4) straight - ram or otherwise; 5) non-kosher animal; 6) cow. The first four categories are used with a bracha, the fifth without a bracha, and the last, not at all.
A shofar may be created from the horn of any kosher male animal from the Bovidae family except for cattle, which is specifically excluded. In practice two species are generally used: the Ashkenazi shofar is a domestic ram (see sheep), while the Sefardi shofar is a kudu.
Bovidae horns are made of keratin (the same material as human toenails and fingernails). An antler, on the other hand, is not a horn but solid bone. Antlers cannot be used as a shofar because they cannot be hollowed out.
A crack or hole in the shofar affecting the sound renders it unfit for ceremonial use. A shofar may not be painted in colors, but it may be carved with artistic designs (Shulkhan Arukh, Orach Chayim, 586, 17). Shofars (especially the Sephardi shofars) are often plated with silver across part of their length for display purposes, although this invalidates them for use in religious practices. According to Jewish law women and minors are exempt from the commandment of hearing the shofar blown (as is the case with any positive, time-bound commandment), but they are encouraged to attend the ceremony.
The horn is flattened and shaped by the application of heat, which softens it. A hole is made from the tip of the horn to the natural hollow inside. It is played much like a European brass instrument, with the player blowing through the hole, causing the air column inside to vibrate. Sephardi shofars usually have a carved mouthpiece resembling that of a European trumpet or French horn, but smaller. Ashkenazi shofars do not.
Because the hollow of the shofar is irregular in shape, the harmonics obtained when playing the instrument can vary: rather than a pure perfect fifth, intervals as narrow as a fourth, or as wide as a sixth may be produced.
Ten appropriate verses from the Bible are recited at each repetition, which ends with a benediction. Over time doubts arose as to the correct sound of the teruah. The Talmud is uncertain whether it means a moaning/groaning or a staccato beat sound. Shevarim was supposed to be composed of three connected short sounds; the teruah of nine very short notes divided into three disconnected or broken sequences of three notes each. The duration of the teruah is equal to that of the shevarim; and the tekiah is half the length of either. This doubt as to the nature of the real teruah, whether it was simply a moan, a staccato or both, necessitated two near-repetitions to make sure of securing the correct sound.
The sequence of the shofar blowing is thus tekiah, shevarim-teruah, tekiah; tekiah, shevarim, tekiah; tekiah, teruah, and then a final blast of "tekiah gadola" which means "big tekiah," held as long as possible. This formula makes thirty sounds for the series, with tekiah being one note, shevarium three, and teruah nine. This series of thirty sounds is repeated twice more, making ninety sounds in all. The trebling of the series is based on the mention of teruah three times in connection with the seventh month (Lev. xxiii, xxv; Num. xxix), and also on the above-mentioned division of the service into malchiyot, zichronot, and shofarot. In addition to these three repetitions, a single formula of ten sounds is rendered at the close of the service, making a total of 100 sounds. According to the Sephardic tradition, a full 101 blasts are sounded, corresponding to the 100 cries of the mother of Sisera, the Cannanite general who did not make it home after being assassinated by the biblical Yael (Judges 5:28). One cry is left to symbolize the legitimate love of a mother mourning her son.
During the Ottoman and the British occupation of Jerusalem, Jews were not allowed to sound the shofar at the Western Wall. After the Six Day War, Rabbi Shlomo Goren famously approached the wall and sounded the shofar.
In pop music, the shofar is used by the Israeli Oriental metal band Salem in their adaptation of "Al Taster" psalm. The late trumpeter Lester Bowie played a shofar with the Art Ensemble of Chicago. In Joey Arkenstat's album Bane, the former bassist for Phish is credited for playing the shofar. In the musical "Godspell", the first act opens with cast member David Haskell blowing the shofar, in preparation for singing "Prepare Ye the Way of the Lord." In his performances, Israeli composer and singer Shlomo Gronich uses the shofar to produce a very wide range of notes.