"..otherwise the land will vomit you out also for having defiled it.."

The Lord said to Moses, "Speak to the Israelites and tell them: I, the Lord, am your God. You shall not do as they do in the land of Egypt, where you once lived, nor shall you do as they do in the land of Canaan, where I am bringing you; do not conform to their customs. My decrees you shall carry out, and my statutes you shall take care to follow. I, the Lord, am your God. Keep, then, my statutes and decrees, for the man who carries them out will find life through them. I am the Lord. "None of you shall approach a close relative to have sexual intercourse with her. I am the Lord. You shall not disgrace your father by having intercourse with your mother. Besides, since she is your own mother, you shall not have intercourse with her. You shall not have intercourse with your father's wife, for that would be a disgrace to your father. You shall not have intercourse with your sister, your father's daughter or your mother's daughter, whether she was born in your own household or born elsewhere. You shall not have intercourse with your son's daughter or with your daughter's daughter, for that would be a disgrace to your own family. You shall not have intercourse with the daughter whom your father's wife bore to him, since she, too, is your sister. You shall not have intercourse with your father's sister, since she is your father's relative. You shall not have intercourse with your mother's sister, since she is your mother's relative. You shall not disgrace your father's brother by being intimate with his wife, since she, too, is your aunt. You shall not have intercourse with your daughter-in-law; she is your son's wife, and therefore you shall not disgrace her. You shall not have intercourse with your brother's wife, for that would be a disgrace to your brother. You shall not have intercourse with a woman and also with her daughter, nor shall you marry and have intercourse with her son's daughter or her daughter's daughter; this would be shameful, because they are related to her. While your wife is still living you shall not marry her sister as her rival; for thus you would disgrace your first wife. "You shall not approach a woman to have intercourse with her while she is unclean from menstruation. You shall not have carnal relations with your neighbor's wife, defiling yourself with her. You shall not offer any of your offspring to be immolated to Molech, thus profaning the name of your God. I am the Lord. You shall not lie with a male as with a woman; such a thing is an abomination. You shall not have carnal relations with an animal, defiling yourself with it; nor shall a woman set herself in front of an animal to mate with it; such things are abhorrent.
"Do not defile yourselves by any of these things by which the nations whom I am driving out of your way have defiled themselves. Because their land has become defiled, I am punishing it for its wickedness, by making it vomit out its inhabitants. You, however, whether natives or resident aliens, must keep my statutes and decrees forbidding all such abominations by which the previous inhabitants defiled the land; otherwise the land will vomit you out also for having defiled it, just as it vomited out the nations before you. Everyone who does any of these abominations shall be cut off from among his people. Heed my charge, then, not to defile yourselves by observing the abominable customs that have been observed before you. I, the Lord, am your God."  (Leviticus 18: 1-30).

And now floods.