Kiddushin 78A

– זונה משוי לה, חללה לא משוי לה. חזר ובא עליה ⁠– עשאה חללה.

renders her a zona, as he was forbidden to her, but he does not render her a ḥalala, since her status as a zona does not result from a prohibition specific to the priesthood, but due to the prohibition of a forbidden relative. If her brother, or any other priest, again had sex with her, he thereby makes her a ḥalala, in accordance with the halakha pertaining to a priest who has sex with a zona.

אמר רב יהודה: כהן גדול באלמנה לוקה שתים, אחת משום ״לא יקח״, ואחת משום ״לא יחלל״. ולילקי נמי משום ״לא יחלל זרעו״! בשלא גמר ביאתו.

§ Rav Yehuda says: A High Priest who has sex with a widow is flogged two sets of lashes, one set due to transgressing the prohibition of: “A widow, or one divorced, or a ḥalala, or a zona, these should he not take” (Leviticus 21:14), and one set due to transgressing the prohibition of: “And he should not profane” (Leviticus 21:15), since he profanes the woman with whom he has sex. The Talmud asks: And let him also be flogged with a third set of lashes due to the complete phrase: “He should not profane his offspring,” because the offspring resulting from that act of sex is a ḥalal. The Talmud answers: It is referring to a situation where he did not complete his act of sex. Since this act does not lead to pregnancy, he is not flogged for profaning his offspring.

מתיב רבא: אלמנה וגרושה לוקה משום שני שמות, מאי לאו שני שמות ותו לא?

Rava raises an objection against Rav Yehuda’s statement from a Mishnah (Makkot 13a): A High Priest who has sex with a widow who was previously a divorcée is flogged due to two labels of prohibitions. What, is it not stating that he is flogged due to two labels and no more? This indicates that he receives only one flogging for each prohibition, and not two as Rav Yehuda taught.