Because people tend to use the bible and other such 'evidence' as it suits them. Good Q, btw ++

Some of the taboos that are ignored now are: intercourse during menstruation, celibacy, exogamy (marriage with non-Jews), naming sexual organs, nudity (under certain conditions), masturbation (some Christians still condemn this), birth control (some Christians still forbid this). The Bible regarded semen and menstrual blood as unclean, which most of us do not. The Bible also permitted behaviors that we today condemn: prostitution, polygamy, levirate marriage, sex with slaves, concubinage, treatment of women as property, and very early marriage (for the girl, age 11-13). And yet, the Bible is used to say homosexuality is wrong? Where is the justification?

Well, not everyone cares what the Bible has to say about anything. It isn't a part of all religions. Having said that, the outspoken believers who are vastly interested in regulating others' behavior pick and choose like they were at a buffet table. They only pick out what suits them.

Because without hand-picked (and usually misinterpreted) Bible passages, there's really no good defense against accepting homosexuality as natural.

Short answer, they can't. Your question made me think of this one. If sex is just for procreation, why does the desire continue even after we've had our children?

Logic doesn't apply to religious fundamentalists. It's kind of a square peg/round hole issue.

Because an Authoritarian personality will accept all sorts of contradictions to maintain deference to a Higher Authority (whether it is a dictator or a deity). http://www.salon.com/opinion/greenwald/2007/09/03/sowell/index.html . . http://www.godhatesshrimp.com/ . .

You answer your own question here. The Bible says one thing while "some Christians" do another thing. Gods word is clear and true. Some organizations that call themselves Christian misrepresent what the Bible says or at least, they pick and choose what they will obey. That is why Jesus said of such ones, In Matthew Chapter 6:13-23 “Go in through the narrow gate; because broad and spacious is the road leading off into destruction, and many are the ones going in through it; whereas narrow is the gate and cramped the road leading off into life, and few are the ones finding it. “Be on the watch for the false prophets that come to YOU in sheep’s covering, but inside they are ravenous wolves. By their fruits YOU will recognize them. Never do people gather grapes from thorns or figs from thistles, do they? Likewise every good tree produces fine fruit, but every rotten tree produces worthless fruit; a good tree cannot bear worthless fruit, neither can a rotten tree produce fine fruit. Every tree not producing fine fruit gets cut down and thrown into the fire. Really, then, by their fruits YOU will recognize those [men]. “Not everyone saying to me, ‘Lord, Lord,’ will enter into the kingdom of the heavens, but the one doing the will of my Father who is in the heavens will. Many will say to me in that day, ‘Lord, Lord, did we not prophesy in your name, and expel demons in your name, and perform many powerful works in your name?’ And yet then I will confess to them: I never knew YOU! Get away from me, YOU workers of lawlessness”

as some have already alluded to, unfortunately, there are a lot of Christians (not all, but those who use the Bible to justify bigotry) that treat the Bible like a fast food menu. They pick what appeals to them and ignore the rest.

the bible, tho fictional, is a weapon wielded by bigoted hate mongerors to get others to side with their homophobia

Oh, well that is part of the latest movement. Notice I said "movement" and did not say "Christian movment." Yes, we will take this command from column A and these from column B. We will ignore anything in column C and go to the church of Burger King where we can have it our way!

Oh, well that is the christian that says, "I will take one from column 'a' and two from column 'b'." I want a little hyprocracy on the side and plenty of covetting my neighbors wife. But, it does not work that way.

We live in a culture where people think they can have it their way. They discount passages that say you should not get tattoos or piercings by saying that times were different then. "Hold the pickles, hold the lettuce, special orders don't upset us, all we ask is that you let us serve it your way!" The Burger King of christian beliefs.

they can't these people are called false teachers, false prophets, and posers. really the first commandment after "the fall" was to replenish the earth. can two men do this? two women? I also know what your getting at here, solomon had a thousand women total, in ecles. he concluded he was wrong. that it was meaningless. but for a minute understand the old covenant. picture yourself sacrificing animals, how long would it take to be the status quo. commercialized, no big deal, how much can you relate to animal. then you look at jesus, no sin. then you look at yourself. oh what a horrible person I am. here is what he taught. love and getting to heaven. the conclusion is this jesus continually says beware of false teachers. every letter the apostles wrote, beware of false teachers. do not take mans word, read for yourself. before i believed never went to church as a kid. read and studied on my own, with many things to compare and common sense and logic.

Well, this answer will not be popular with most of the people who have commented on this question, yet I feel I must make at least an attempt to answer the question. You are quite correct when you say there are many “taboos” regarding sexual behavior in the bible. What you need to differentiate is the difference between what the bible teaches and what certain ”Christian” sects preach. I use the term Christian in parentheses because, quite frankly, many so called Christian churches have turned away from the clear teaching the bible has regarding sexual behavior and adopted a different world view in conflict with biblical teaching. Is the bible consistent in its teaching about homosexual behavior? Let’s examine it. Leviticus says, Lev 18:22 Thou shalt not lie with mankind, as with womankind: it is abomination. Lev 18:29 For whosoever shall commit any of these abominations, even the souls that commit them shall be cut off from among their people. In this case to be cut off come from the Hebrew word karath (Strongs H3772) meaning to be destroyed. Two chapters later in Leviticus, it says, Lev 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. This seems to be rather clear that the Old Testament is consistent with its view on homosexuality. There are those who have raised the question about prostitution being permissible in the bible. It is true that some of the patriarchs did engage in sexual immorality. Engaging in prostitution, adultery, incest, etc. But in doing so they did not change the bibles stance on the morality of those acts. The bible is consistent in its stance that sexual relations, outside of marriage, is not a moral act. It is in fact a sin. There are those that maintain that the dietary laws advocated in the old testament were done away with in the new testament. And that if those laws were abrogated then the laws pertaining to sexual immorality may also be abrogated. There is no evidence of this being the case. In fact we have just the opposite. In Romans we have Paul speaking of sexual behavior, Rom 1:26 For this cause God gave them up unto vile affections: for even their women did change the natural use into that which is against nature: Rom 1:27 And likewise also the men, leaving the natural use of the woman, burned in their lust one toward another; men with men working that which is unseemly, and receiving in themselves that recompence of their error which was meet. And in 1st Corinthians we see, 1Co 6:9 Know ye not that the unrighteous shall not inherit the kingdom of God? Be not deceived: neither fornicators, nor idolaters, nor adulterers, nor effeminate, nor abusers of themselves with mankind, 1Co 6:10 Nor thieves, nor covetous, nor drunkards, nor revilers, nor extortioners, shall inherit the kingdom of God. From these passages we can see that the old and new testaments are consistent with their condemnation of homosexuality and heterosexual sex outside of marriage. It is considered a sin. What actions does the bible recommend with regard to sexually immoral behavior within the church? Those who have committed sin, of any kind, are encouraged to turn away from their past sinful behavior and to seek forgiveness from God. As a case in point I would like to use. Jesus was presented with a woman caught in the act of committing a sexual sin, adultery. The penalty prescribed under the law of Moses was death by stoning. After Jesus had the crowd disperse he spoke to the woman. Joh 8:10 When Jesus had lifted up himself, and saw none but the woman, he said unto her, Woman, where are those thine accusers? hath no man condemned thee? Joh 8:11 She said, No man, Lord. And Jesus said unto her, Neither do I condemn thee: go, and sin no more. Jesus told her that he would not call on her to pay the penalty for her sin. He recognizedher repentance, but he also recognized the sin did exist and called on her to not sin again. In the same way the correct calling of the church would be to call on homosexuals to repent their sin, and to no longer engage in the sinful act of homosexuality. In the same way, those who engage in fornication or heterosexual relations outside of marriage are also called upon to repent and sin no more. Should the church bless the sinful acts of its members, or allow non repentant sinners places of authority within the church? The answer is clearly no. I cite as precedent 1 Corinthians chapter 5; Co 5:1 It is reported commonly that there is fornication among you, and such fornication as is not so much as named among the Gentiles, that one should have his father's wife. 1Co 5:2 And ye are puffed up, and have not rather mourned, that he that hath done this deed might be taken away from among you. 1Co 5:3 For I verily, as absent in body, but present in spirit, have judged already, as though I were present, concerning him that hath so done this deed, 1Co 5:4 In the name of our Lord Jesus Christ, when ye are gathered together, and my spirit, with the power of our Lord Jesus Christ, 1Co 5:5 To deliver such an one unto Satan for the destruction of the flesh, that the spirit may be saved in the day of the Lord Jesus. 1Co 5:6 Your glorying is not good. Know ye not that a little leaven leaveneth the whole lump? If someone willingly continues to engage in sexually immoral behavior, then he is to be removed from the fellowship of the church. He is certainly not to placed into any position of authority within it. From this we can see that those so called “Christian churches” which not only marry homosexuals but place them in positions as priests or bishops are in clear opposition to the teachings of the bible and of Jesus Christ. They are heretics, and schismatics. Now if you want to follow non Christian traditions, fine. Be a Shinto or a Muslim or a Buddhist, but don’t go calling yourself a Christian.