TT #321 · 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: כַּאֲשֶׁר צִוְּךָ ה׳ אֱלֹהֶיךָ.
English: ‘As the Eternal your God has commanded you’ – elsewhere.
Derash linking to prior commands (Sifrei) — the verse recalls the earlier mitzvah of destroying the seven nations.
The herem of the seven nations is the same command already given; this verse reaffirms it in the context of war.