And the Lord your God will drive out those nations before you little by little; you will be unable to destroy them at once, lest the beasts of the field become too numerous for you. (Deuteronomy 7:22)
The law and the prophets are a shadow of the good things that were to come in the gospels of Christ.(1) Those nations that were to be driven out before the nation of Israel represent the sin that is to be driven out of the believer. When we came to the saving knowledge of Christ, we were instantly forgiven and given the promise of heaven. Nevertheless, without a doubt, there were and are things in our lives that need to be driven out of us, like those nations that were driven out before Israel little by little.
We have so many hidden and inherent sins in us that the Lord in His grace and mercy drives them out little by little. After more than three decades of walking with the Lord, He still is removing my sin nature. It is for this reason we are instructed to die daily. (2) It may not be: Hittites, Girgashites, Amorites, Canaanites, Perizzites, Hivites, or Jebusites; but it will be lust, hatred, pride, arrogance, jealousy, speculation, and all that exalts itself against the knowledge of God.