How does the Earth react to the presence of man? The Land of Canaan did not react very well to the presence of the Canaanites because of their sin, and so vomited the people out of the land. Thus, the Lord warned Israel,
“You shall therefore keep My statutes and My judgments, and shall not commit any of these abominations, either any of your own nation or any stranger who dwells among you (for all these abominations the men of the land have done, who were before you, and thus the land is defiled), lest the land vomit you out also when you defile it, as it vomited out the nations that were before you. For whoever commits any of these abominations, the persons who commit them shall be cut off from among their people. Therefore you shall keep My ordinance, so that you do not commit any of these abominable customs which were committed before you, and that you do not defile yourselves by them: I am the Lord your God” (Leviticus 18:26–30).
In time, Israel did as the Canaanites did, and the Land of Canaan vomited out the Israelites. This is why Christians must remember that they are the salt of the earth and the light of the world, for by our presence we can keep this from happening to our various nations.