Some say a different version of this statement: Rabbi Ḥiyya bar Abba said that Rabbi Yoḥanan said: A man who removes the hair of the armpit or the pubic hair is flogged, due to the prohibition: “A man shall not put on a woman’s garment” (Deuteronomy 22:5). The Gemara raises an objection from a baraita: The removal of hair is not prohibited by Torah law but by rabbinic law. How then does Rabbi Yoḥanan say that he is flogged, which by definition is a punishment for individuals who have transgressed a Torah law? The Gemara answers: It was he who said this halakha in accordance with the opinion of that tanna, as it is taught in a baraita: A man who removes the hair of the armpit or the pubic hair violates the prohibition of: “A man shall not put on a woman’s garment.”

The Gemara asks: And what does the first tanna, who holds that the prohibition is by rabbinic law, learn from this verse: “A man shall not put on a woman’s garment”? The Gemara answers: He requires it for that which is taught in the baraita, where it states: “A woman shall not wear that which pertains to a man, and a man shall not put on a woman’s garment, for whoever does these things is an abomination to the Lord your God” (Deuteronomy 22:5). What is the meaning when the verse states this? If it teaches only that a man may not put on a woman’s garment, and a woman may not wear a man’s garment, it is already stated in explanation of this prohibition that “it is an abomination to the Lord your God,” and there is no abomination here in the mere act of wearing a garment.

Rather, it means that a man may not wear a woman’s garment and thereby go and sit among the women; and a woman may not wear a man’s garment and sit among the men. Rabbi Eliezer ben Ya’akov says: From where is it derived that a woman may not go out with weapons to war? The verse states: “A woman shall not wear that which pertains to a man, and a man shall not put on a woman’s garment,” which indicates that a man may not adorn himself with the cosmetics and ornaments of a woman, and similarly a woman may not go out with weapons to war, as those are for the use of males. Rabbi Yoḥanan’s ruling follows this opinion.

§ Rav Naḥman said: For a nazirite, it is permitted to shave armpit hair. The Gemara comments: And the halakha is not in accordance with his opinion. The Gemara reports that the Sages said to Rabbi Shimon bar Abba: We have observed that Rabbi Yoḥanan does not have armpit hairs, despite his own ruling that it is prohibited to shave them. He said to them: They fell out due to old age.

The Gemara relates: There was a certain person who committed a transgression and was found liable to receive lashes before Rabbi Ami. When they removed his clothes to flog him, his armpit was exposed, and Rabbi Ami saw that he had not shaved his armpit hair. Rabbi Ami said to his attendants: Leave him; this is one of those who are meticulous in observance of mitzvot. We can see this is so, as he is particular about prohibitions that ordinary people do not observe.

Rav raised a dilemma before Rabbi Ḥiyya: What is the halakha with regard to shaving armpit hair? He said to him: It is prohibited. Rav said to him: But it grows and is uncomfortable. Rabbi Ḥiyya said to him: Son of nobles [bar paḥtei], this hair has a limited time. Whenever a hair grows too long it falls out, and therefore there is no concern that one’s armpit hair will become too long.

Rav raised another dilemma before Rabbi Ḥiyya: What is the halakha with regard to rubbing armpit hair and thereby removing it manually? Rabbi Ḥiyya said to him: It is prohibited. Rav continued to ask: What is the halakha with regard to rubbing armpit hair indirectly with one’s garment? Rabbi Ḥiyya said to him: It is permitted. Some say that this was not Rav’s question; rather, he raised the following dilemma before him: What is the halakha with regard to rubbing the armpit with one’s garment during prayer? Rabbi Ḥiyya said to him: It is prohibited. The Gemara comments: And the halakha is not in accordance with his opinion in this case.