TT #320 · Parashas Shoftim · Seventh Aliyah · Passuk 20:17
For you shall utterly destroy them – the Chitti and the Emori, the Kenaani and the Perizzi, the Chivvi and the Yevusi – as the Eternal your God has commanded you.
Torah Temimah points to Sifrei Devarim 200.
TT lemma: הַחֲרֵם תַּחֲרִימֵם.
English: ‘You shall utterly destroy them’ – a commandment to devote them to destruction.
Derash on the herem (Sifrei) — the doubled language emphasizes the absolute duty.
The seven nations of the Land must be completely devoted to destruction; this is an obligatory war.