Which mitzvot are slaves who have been immersed obliged to follow?

Question

R Steinsaltz notes in his explanation of a passage in Yevamot 45b

that a gentile slave purchased by a Jew must be circumcised and then immersed in a ritual bath by being immersed for the sake of slavery, he takes on the status of a full slave, which, among other things, obligates him to keep certain mitzvot. However, if the slave, or any gentile, is immersed for the sake of conversion, he then becomes a full Jew and fully obligated in mitzvot like any other Jew.

Which mitzvot is the slave obliged to follow and why? For example, the mitzvot he follows must be other than just the Noahide laws, so does he follow them because he is now "half-Jewish"?

Answer 1

The general rule is, as cited in the Gemara (Chagiga 4a) that the obligations of a slave are equivalent to those of a women.

כׇּל מִצְוָה שֶׁהָאִשָּׁה חַיֶּיבֶת בָּהּ עֶבֶד חַיָּיב בָּהּ כׇּל מִצְוָה שֶׁאֵין הָאִשָּׁה חַיֶּיבֶת בֵּהּ אֵין הָעֶבֶד חַיָּיב בָּהּ דְּגָמַר ״לָהּ״ ״לָהּ״ מֵאִשָּׁה

As such, a slave would be exempt from any time bound mitzvos.

However, there are some exceptions to this rule:

• The obligation to procreate (פרו ורבו). Although a woman is exempt from the obligation of פרו ורבו (according to most opinions; see Yevamos 65b), some Rishonim posit that a slave is obligated (see Tosfos Chagiga 2b based on Yerushalmi Moed Katan (1:1).

• Circumcision (ברית מילה): Women are not obligated in circumcision. However, some opinions obligate a male slave in circumcision. (See R' Akiva Eiger to YD 267, and Sha'ar Hamelech on Rambam Milah 1)

• The Prohibition of Lo Sakifu (הקפת הראש וזקן): Women are not prohibited from using a razor in certain parts of the body that men are prohibited from. According to the Rambam (see R' Akiva Eiger ad loc for discussion), a male slave is prohibited.

• Reading of Megillas Esther (קריאת המגילה): Although women are obligated (אף הם היו באותו הנס), the Beis Yosef (OC 689) derives from the wording of Rambam (Megila 1:1, see Lechem Mishnah) that slaves are not obligated. The same is true of any time-bound mitzvah which women are obligated only because of אף הם היו באותן הנס, such as Chanukah or the Four Cups.

Answer 2

The same mitzvos that a Jewish woman is obligated in, as it says in Chagigah 4a:

כׇּל מִצְוָה שֶׁהָאִשָּׁה חַיֶּיבֶת בָּהּ עֶבֶד חַיָּיב בָּהּ כׇּל מִצְוָה שֶׁאֵין הָאִשָּׁה חַיֶּיבֶת בֵּהּ אֵין הָעֶבֶד חַיָּיב בָּהּ דְּגָמַר ״לָהּ״ ״לָהּ״ מֵאִשָּׁה

With regard to every mitzva in which a woman is obligated, a slave is also obligated in that mitzva; and with regard to every mitzva in which a woman is not obligated, a slave is not obligated in it either. The reason for this principle is that it is derived by means of a verbal analogy between the phrase: “To her” (Leviticus 19:20), written with regard to a designated maidservant, and the phrase: “To her” (Deuteronomy 24:3), written with regard to a divorced woman.

Answer 3

R Jack Abramowitz answers your question in his review of this commandment

A Canaanite slave is like a partial convert; he keeps the same level of mitzvos that a Jewish woman keeps, meaning that he is exempt from positive mitzvos that must be performed at a particular time, such as tzitzis and tefillin.

See also Sefer Hachinuch 347

And they, may their memory be blessed, said regarding a Canaanite slave (Yevamot 48b) that his master takes care of him up to twelve months; if he wants to deny and abandon idolatry, get circumcised and immerse for the sake of slavery and accept the commandments that Jewish women are obligated, it is good [...]

For more on the status of these slaves and the respect due to them, see Mishne Torah Hilchot Avadim ch. 9

PS. "Despite the name, the law of the eved K’naani was not limited to Canaanites; the term is merely in contradistinction to the eved Ivri."