Prescribed method of blowing the ram's horn on the Jewish New Year
The blowing of the shofar (, ) is a ritual performed by Jews on Rosh Hashanah. The shofar is a musical horn, typically made of a ram's horn. Jewish law requires that the shofar be blown 30 times on each day of Rosh Hashanah, and by custom it is blown 100, 101 or 102 times on each day.
Speak unto the children of Israel, saying: In the seventh month, in the first day of the month, shall be a solemn rest unto you, a memorial proclaimed with the blast of horns, a holy convocation.
Modern practice.
Initially, the blasts made by the ram's horn were blown during the first standing prayer (Amidah) on the Jewish New Year, but by a rabbinic edict, it was enacted that they be blown only during the Mussaf-prayer, because of an incident that happened, whereby congregants who blew the horn during the first standing prayer were suspected by their enemies of staging a war-call and were massacred. Even though the underlining motive for the rabbinic enactment was no longer prevalent in ensuing generations, their enactment still stands and is practised by all Jewish communities to this very day, to blow the ram's horn only during the Mussaf-prayer.
Types of blast.
The following blast are blown on Rosh Hashanah:
Combinations of blasts.
The blasts are blown in the following set groups:
Place in the prayer service.
In Ashkenazi and Sephardic communities, it is customary to hear 100 or 101 or 102 sounds in the synagogue on Rosh Hashanah morning, although the minimum requirement is to hear 30 sounds. The sounds are scheduled as follows:
According to all opinions, the mitzvah is fulfilled by hearing the initial set of 30 blasts. Thus, if a person cannot attend the synagogue prayers, they will commonly arrange for a shofar blower to visit and blow only 30 blasts for them.
Additional laws.
Duration of the notes.
Among Ashkenazi and Sephardic communities, the "teruah" is blown as nine very short notes, while the "shevarim" is blown as three longer notes, each equal in duration to three short notes. The "tekiah" must be longer than the blast which it comes before and after. Thus the "tekiah" must be more than 9 short notes in duration when blowing "TaRaT" or "TaShaT", and more than 18 short notes when blowing "TaShRaT".
The Shulchan Aruch rules that the minimum length of a "teruah" and "tekiah" are identical, but agrees that a longer "teruah" is also valid. In Yemen, the practice was to make the "teruah" double the length of a "tekiah". Each community is advised to follow its ancestral tradition.
Pausing between "shevarim" and "teruah".
When "shevarim" and "teruah" are blown together, a dispute exists whether they must be blown in a single breath, or whether one may pause (for a duration of no longer than a breath) between them. The Shulchan Aruch suggests that "one who fears God" should blow in a single breath before Mussaf, and with two breaths during Mussaf. The Chazon Ish adopted this practice. However, general Ashkenazi custom is to always stop for breath between "shevarim" and "teruah", both before and during Mussaf (but not between the three blasts of "shevarim"), although some communities which follow the mainstream Ashkenazic custom still do the blasts after musaf in one breath.
Rabbi Yihya Saleh, explaining the Yemenite custom, wrote that a breath is taken between "shevarim" and "teruah", both before and during Mussaf. In this regard, the Yemenite practice was more lenient than that of the Shulchan Aruch.
History.
Initial 9 blasts.
The Torah twice defines Rosh Hashanah as a day of "teruah" or horn-blowing (, ), without specifying exactly how this is to be done.
The rabbis of the Talmud concluded that a shofar must be used for this blowing, and that each "teruah" must be preceded and followed by a "tekiah". Since the word "teruah" appears three times in the Torah in connection with holidays of the seventh month, the rabbis concluded that a "teruah" must be blown three times, making a total of nine blasts (three sets of "tekiah"-"teruah"-"tekiah"). The three sets also correspond to the three special blessings of Mussaf: "malchiyot", "zichronot", and "shofarot".
From 9 to 30 blasts.
In the Talmudic era, doubts arose regarding the correct sound of the "teruah" blast - whether it should be a series of short, lilting blasts similar to a person moaning (now known as "shevarim"), or else a staccato beat sound similar to a person whimpering (now known as "teruah"), or else a combination of the two sounds ("shevarim-teruah"). Therefore, Rav Abbahu of Caesarea (3rd century CE), ruled that shofar blowing should be performed according to each of the three possibilities:
If "tekiah, shevarim-teruah, tekiah" is considered to be four blasts, then Rabbi Abbahu's requirement makes for a total of 30 blasts.
According to another opinion, Rabbi Abbahu instituted a total of 12 rather than 30 blasts, specifically "tekiah, shevarim-teruah, tekiah" repeated three times. However, modern halacha accepts the opinion that 30 blasts are blown.
From 30 to 100 blasts.
The Talmud specifies that the shofar is blown on two occasions on Rosh Hashana: once while "sitting" (before the Mussaf prayer), and once while "standing" (during the Mussaf prayer). This increases the number of blasts from the basic requirement of 30, to 40, 42, or 60, based on the above-mentioned opinions.
The "Arukh" mentions a custom to blow 100 blasts: 30 before Mussaf, 30 during the Mussaf silent prayer, 30 during the cantor's loud repetition of Mussaf, and 10 more after Mussaf. The final 10 blasts are by tradition dating to the Geonim, and in some communities are blown in the middle of "Kaddish Tiskabal." Blowing 100 (or 101 or 102) blasts is nearly universal today (with the exception of many Yemenite and Spanish Portuguese Jews), although many congregations omit the 30 blasts in the silent prayer, and instead blow 40 after Mussaf, and some communities do only 10 (or 12) during the repetition and blow 60 afterwards. 
The number 100 in the "Arukh" is intended to correspond to the tears which Sisera's mother is said to have shed when her son was killed in battle. (The Hebrew word used to describe her wailing is "" ( ;templatestyles src="Script/styles_hebrew.css" / ;ותיבב‎); this is cognate to "yevava" ( ;templatestyles src="Script/styles_hebrew.css" / ;יבבה‎), the Aramaic translation of "teruah".) The short Biblical story of Sisera's mother contains 101 letters; while the Arukh only mentions 100 blasts. This discrepancy is explained by saying that while each shofar blast is intended to "nullify" one of her cries due to hatred of Israel, nevertheless we leave her one tear out of recognition of the pain suffered by any bereaved mother. In any case, Sephardic communities typically blow 101 blasts, with the 101st symbolizing her legitimate mourning.
Symbolic meaning.
Maimonides wrote that even though the blowing of the shofar is a Biblical statute to praise the God,it is also a symbolic "wake-up call", stirring Jews to mend their ways and repent: "Sleepers, wake up from your slumber! Examine your ways and repent and remember your Creator."
Rabbi Abraham Isaac Kook suggested that the doubt whether the shofar sound is supposed to be short, intermittent blasts ("Shevarim"), like a person groaning in remorse, or a series of short, staccato bursts ("Teru'ah"), like the uncontrolled wailing of a person in extreme anguish and grief, may be connected to Maimonides’ explanation. Some people are moved to better themselves due to an intellectual recognition that something was seriously amiss in their lives. Their shofar sounds – what motivates them to repent – are the heavy sighs and groans of the introspective individual, the "Shevarim". For others, the stimulus comes from the heart. They are moved by the overwhelming pain and anguish of a person who has lost his way – the emotional outburst and wailing of the "Teru’ah". The most effective form of repentance, however, utilizes the strengths of both faculties, the emotions and the intellect, combining together the "Shevarim" and the "Teru'ah".
References.
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