“And when the LORD thy God shall deliver them before thee; thou shalt smite them, and utterly destroy them; thou shalt make no covenant with them, nor shew mercy unto them:”
King James Version (KJV)
7:1 Seven nations - There were ten in #Gen 15:19 |- 21. But this being some hundreds of years after, it is not strange if three of them were either destroyed by foreign or domestick wars, or by cohabitation and marriage united with, and swallowed up in the rest.
7:4 To serve other Gods - That is, there is manifest danger of apostacy and idolatry from such matches. Which reason doth both limit the law to such of these as are unconverted (otherwise Salmon married Rahab, #Matt 1:5|) and enlarge it to other idolatrous nations, as appears from #1Kin 11:2 Ezra 9:2 Neh 13:23|.