申命記 20:17 哈拉卡：Mishneh Torah, Kings and Wars, Gray Matter III, Mishneh Torah, Positive Mitzvot & Sefer HaChinukh

It is a Positive Commandment to exterminate the Seven Nations, as it says, “surely, you shall destroy them” (Deut. 20:17). Anyone who comes across any of these nations and fails to kill them violates a Negative Commandment, as it says, “you shall not keep alive any soul” (Deut. 20:16). Nonetheless, they have already all been destroyed and their memory forgotten.

Rav Schachter summarizes the many opinions regarding the Rambam’s celebrated omission of the mitzvah of living in Israel from his list of the 613 mitzvot. He presents opinions (cited by Sdei Chemed Ma’arechet Eretz Yisrael 2) that the Rambam believes that the mitzvah to live in Israel is rabbinic and therefore does not list it as one of the 613 mitzvot. Rav Schachter then cites the Avnei Neizer (in his aforementioned responsum), who asserts that once the Rambam counted the mitzvah of conquering the seven nations who lived in Israel prior to the conquest of Yehoshua (Devarim 20:17), he did not find it necessary to count the actual conquest and settlement as a separate mitzvah.

To exterminate the seven Canaanite nations from the land of Israel, as it is said, “But thou shalt utterly destroy them….” (Deut. 20:17).