"Prohibited to you (For marriage) are:- Your mothers, daughters, sisters; father's sisters, Mother's sisters; brother's daughters, sister's daughters; foster-mothers (Who gave you suck), foster-sisters; your wives' mothers; your step-daughters under your guardianship, born of your wives to whom ye have gone in,- no prohibition if ye have not gone in;- (Those who have been) wives of your sons proceeding from your loins; and two sisters in wedlock at one and the same time, except for what is past; for Allah is Oft-forgiving, Most Merciful;" - Quran 4:23 (read more)

"Narrated 'Abdullah bin 'Umar : The Jew brought to the Prophet a man and a woman from amongst them who have committed (adultery) illegal sexual intercourse. He ordered both of them to be stoned (to death), near the place of offering the funeral prayers beside the mosque." - Sahih Bukhari 7:62:64 (read more)

"It is said that the kaafirs, Jews, Christians and communists in the east and the west all keep dogs, Allaah forbid. Each one takes his dog with him and cleans it every day with soap and other cleansing agents. But even if he were to clean it with the water of all the seas in the world and all the soap in the world, it would never become pure! Because its impurity is inherent, and inherent impurity cannot be cleansed except by destroying it and erasing it altogether." - Shaykh Ibn ‘Uthaymeen