Deuteronomy 7:22

And the Lord your God shall consume these nations before you by little and little: you shall not be able to consume them speedily, lest the land become desert, and the wild beasts of the field be multiplied against you.

And the Lord thy God will put out those nations before thee by little and little: thou mayest not consume them at once, lest the beasts of the field increase upon thee.

Yahweh your God will cast out those nations before you little by little. You may not consume them at once, lest the animals of the field increase on you.