This mitzvah prohibits an ordinary Kohen from marrying a divorcee. Because the Kohen is sanctified for the service of Hashem, he must maintain a higher level of purity in his marital relationship. While a Kohen is permitted to marry a widow, he is forbidden from marrying a divorcee, a zonah (woman with forbidden relations), or a chalalah (woman of desecrated priestly lineage). This mitzvah highlights the special holiness of the priesthood and the need for his household to reflect that sanctity.

Commentary & Classical Explanation:

• Rambam (Hilchot Issurei Bi’ah 17:1–2): Codifies that all Kohanim are prohibited from marrying divorcees, unlike Yisraelim, for whom this is permitted.
• Sefer HaChinuch (Mitzvah 268): The root is to preserve the spiritual distinction of the Kohanim, ensuring that their family lineage remains pure and honorable.
• Talmud (Yevamot 6a): Derives that although Kohanim may marry widows, they are explicitly prohibited from divorcees, reflecting the Torah’s balance of restrictions.