He himself will consume these nations in your sight, a little at a time, by degrees. You will not be able to destroy them all at once. Otherwise, the wild beasts of the earth might increase against you
Other versions
King James Version
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. English Standard Version
The LORD your God will clear away these nations before you little by little. You may not make an end of them at once, lest the wild beasts grow too numerous for you.New International Version
The LORD your God will drive out those nations before you, little by little. You will not be allowed to eliminate them all at once, or the wild animals will multiply around you.