Because of 2 repeated lines in the bible Leviticus 18:22: " Thou shalt not lie with mankind, as with womankind: it is abomination." Leviticus 20:13:" If a man also lie with mankind, as he lieth with a woman, both of them have committed an abomination: they shall surely be put to death; their blood shall be upon them." The word "Sodomite" and "Gomorrah" is also often refereed to homosexuals, but those are actually names of cities, not an action. Going further, strictly literal, all reference is with men and implied anal sex between men, so anal sex does not apply to women. Much of the laws on sexual behavior where created centuries after the original Biblical writings. All of this is forced the leaders of then chaotic and anarchic Biblical societies in to some strictly defined and sometimes ill conceived order. But despite greater understanding, a much more balanced set of laws, and tolerance, sexual ignorance is still rampant. In 1998 a gay couple was arrested in Houston, TX, charged with centuries old Biblical based laws. It went to SCOTUS where law was struck down, overturning a 1986 ruling. Because so few (3~5%) of people have unique sexual orientation it is easy for them to be bullied by the normal sexual orientated people, yet history is full of great homosexual people who are known for massive contributions to humanity.