Halacha 1
Everyone is obligated to hear the sounding of the shofar: priests, levites, Israelites, converts, and freed slaves. However, women, slaves, and minors are free of the obligation.
A person who is half slave and half free, a tumtum, and an androgynous are obligated [to hear shofar].
Halacha 2
Whoever is not [himself] obligated regarding this matter cannot facilitate the performance of the mitzvah for one who is obligated. Thus, if a woman or a minor blows the shofar, one who hears does not fulfill his obligation.
An androgynous can facilitate the performance of the mitzvah for one of his kind, but not for one who is not of his kind. A tumtum cannot facilitate the performance of the mitzvah [for anyone], whether of his kind or not of his kind, for if [the layer of skin covering] the tumtum's [genitalia] is cut open, it is possible that it will be discovered that the tumtum is a male, but it is possible that it will be discovered that the tumtum is a female.
Halacha 3
A person who is half slave and half free cannot even facilitate the performance of the mitzvah for himself, because the aspect of himself which is a slave cannot facilitate the performance of the mitzvah for the aspect of himself which is free.
How should he fulfill his obligation? He should hear a free man blow the shofar.
Halacha 4
A person who occupies himself with blowing the shofar in order to learn does not fulfill his obligation. Similarly, one who hears the shofar from a person who blows it casually does not fulfill his obligation.
If the person hearing had the intention of fulfilling his obligation, but the person blowing did not have the intention of facilitating the latter's performance of the mitzvah, or the person blowing had the intention of facilitating his colleague's performance of the mitzvah, but the person hearing did not have the intention of fulfilling his obligation, [the person hearing] did not fulfill his obligation. Rather, both the person hearing and the one allowing him to hear must have the [proper] intention.
Halacha 5
If a person blew the shofar with the intention of enabling all those hearing his blowing to perform the mitzvah, and a listener heard while having the intention to fulfill his obligation - even though the person blowing did not have a specific intention that this individual would hear his blowing, nor did he know about him - the listener has fulfilled his obligation, because the blower had in mind all those who heard him.
Accordingly, if a person was traveling on a journey or was sitting in his home and heard the teki'ot from the person leading the congregation, he has fulfilled his obligation if he had that intention, since the leader of the congregation had the intention of enabling the many to fulfill their obligation.
Halacha 6
If the festival of Rosh Hashanah falls on the Sabbath, the shofar is not sounded in every place. [This law was enacted] even though blowing [the shofar] was forbidden only as sh'vut.
It would be appropriate for [the shofar] to be sounded, for a positive commandment of the Torah should supersede sh'vut instituted by the Sages. If so, why is the shofar not sounded?
Because of a decree [of the Sages] lest a person take it in his hands and carry it to a colleague so that the latter can blow for him, and [in the process,] carry it four cubits in the public domain or transfer it from one domain to another, and thus violate a prohibition punishable by being stoned to death. [This is necessary because] all are obligated in the mitzvah of blowing the shofar, but not all are skilled in it.
Halacha 7
Children who have not reached an age at which they can be educated: We need not prevent them from blowing [the shofar] on a Sabbath which is not the festival of Rosh Hashanah, so that they will learn [to blow].
An adult is permitted to be involved in the instruction [of children in the blowing of shofar] on the festival. [This applies] concerning both children who have reached an age at which they can be educated and those who have not reached that age, for blowing [the shofar] is prohibited only as sh'vut.
Halacha 8
When [the Sages] decreed not to sound [the shofar] on the Sabbath, they applied that decree only to places which lacked a court. However, while the Temple was standing and the Supreme Court was seated in Jerusalem, everyone would sound the shofar in Jerusalem throughout the entire period the court held its sessions there.
[This did not apply] to the people of Jerusalem alone. Rather, every city that was within the outer limits of Jerusalem and [whose inhabitants] could:
see Jerusalem - i.e., excluding those within a wadi;
hear the shofar blown in Jerusalem - i.e., excluding those on the mountaintops; and
travel to Jerusalem - i.e., excluding those separated by a wadi from the city
the people of these cities would blow the shofar on the Sabbath as in Jerusalem. However, in the other cities of Israel, they would not sound [the shofar on the Sabbath].
Halacha 9
At present, while the Temple is destroyed, wherever a court whose judges received semichah in Eretz Yisrael permanently holds sessions, the shofar is sounded on the Sabbath. Furthermore, the shofar is sounded on the Sabbath only in a court that has sanctified the new moon. However, the shofar will not be sounded in other courts, even though their judges have received semichah. Also, the shofar is sounded only in the presence of a high court.
It may be sounded during the entire time they are in session. Even after they have begun preparing to rise - as long as they have not risen - the shofar may be sounded before them. However, outside the court, the shofar may not be sounded.
Why is the shofar allowed to be sounded in the court? Because the court is scrupulous [in the observance of the mitzvot] and, in its presence, those who blow the shofar will not carry the shofar in the public domain, for the court will warn the people and inform them.
Halacha 10
In the present age, when we celebrate Rosh Hashanah in the exile for two days, the shofar is sounded on the second day just as it is sounded on the first.
If the first day falls on the Sabbath, those who were not in the presence of a court fit to blow the shofar on the Sabbath may blow the shofar on the second day alone.
Everyone is obligated to hear - Though the Rambam's statements are based on Rosh Hashanah 29a, he makes a slight emendation, adding the expression "to hear," in order to emphasize that the mitzvah is hearing, not blowing, the shofar.
the sounding of the shofar: priests, levites, Israelites, converts - Hilchot Issurei Bi'ah 12:17 states:
and freed slaves. - Hilchot Issurei Bi'ah 14:19 states: "Freed slaves are the same as converts."
However, women, - Women are freed from the obligation to perform mitzvot that are linked to a specific time. Nevertheless, based on Rosh Hashanah 33a, the Shulchan Aruch, Orach Chayim 589:6 states that we are allowed to blow the shofar for them.
The Shulchan Aruch continues that the women should not recite a blessing before hearing the shofar. Those statements are based on the Rambam, Hilchot Tzitzit 3:9 and Chapter 6, Halachah 13 below. The rationale is that the blessing recited before a commandment praises God "for commanding us to..." There is no commandment, either from the Torah or the Sages, requiring women to hear the blowing of the shofar. Hence, they should not recite this blessing.
The Ashkenazic concept differs. The Ramah (based on Tosafot, Rosh Hashanah, ibid.) maintains that women may recite a blessing. Since our Sages explained that the women are granted reward for fulfilling these mitzvot, it is obvious that the commandment is relevant to them and they may say "who commanded us."
slaves - i.e., gentile slaves (עבדים כנעניים), who are required to fulfill only the mitzvot for which women are obligated. (See Hilchot Issurei Bi'ah 12:11, 14:9.) A Jew sold as a slave (עבד עברי) is required to fulfill all the mitzvot.
and minors are free of obligation - Until a person reaches majority, he is not obligated to perform any of the mitzvot. Nevertheless, when a child reaches an age when he can appreciate the mitzvah, his father is obligated to train him to hear shofar as part of his education. (See Hilchot Nachalot 11:9.)
A person who is half slave and half free - In Hilchot Avadim 7:4, the Rambam explains that a slave can reach this status in one of three ways:
Such a slave is considered as having two different natures included in the same person. Thus, the aspect of him which is a free man is obligated to hear the shofar, and the aspect which is a slave is not. See also Halachah 3.
a tumtum - an expression meaning "closed one" in Hebrew. It refers to a person whose genitalia are covered by a layer of skin. Hence, this person's gender cannot be determined without this skin's removal. Thus, there is a doubt whether this person is male or female. However, should this layer of skin be removed and the person's gender be discovered, there is no difference between him and an ordinary person of the same gender. (See Hilchot Ishut 2:25.)
and an androgynous - a term borrowed from the Greek, in which andro means "man," and gynous "woman." It refers to person who has both male and female sexual organs. The Sages were unsure whether to consider such a person a male or a female. (See Hilchot Ishut 2:24 and also the commentary on the following halachah.)
are obligated [to hear shofar] - In the latter two cases, the obligation results from the doubt which exists whether these individuals are male (and hence obligated to hear shofar) or not.