The LORD your God will drive out these nations before you little by little. You will not be enabled to eliminate them all at once, or the wild animals would multiply around you.
Here, I. The caution against idolatry is repeated, and against communion with idolaters: "Thou shalt consume the people, and not serve their gods." Deu 7:16. We are in danger of having fellowship with the works of darkness if we take pleasure in fellowship with those that do those works. Here is also a repetition of the charge to destroy the images, Deu 7:25, Deu 7:26.
Commenting on Deuteronomy 7:12-26
And the Lord thy God will put out those nations before thee by little and little,.... Which is observed for their encouragement, who seeing that all were not destroyed at once, might fear the work would never be thoroughly accomplished; see Exo 23:30, thou mayest not consume them at once; though it was in the power of their hands to do it, there being some...
lest the beasts of the field increase upon thee--(See on Exo 23:29). The omnipotence of their Almighty Ruler could have given them possession of the promised land at once. But, the unburied corpses of the enemy and the portions of the country that might have been left desolate for a while, would have drawn an influx of dangerous beasts.