Homosexuality (also Gayness, Queerness, LGBTness) is a sexual orientation, wherein a man loves a man, or a woman loves a woman, or a small furry creature from Proxima Centauri loves a small furry creature from Proxima Centauri of the same gender. It is doing everyone a favor, as gays are less likely to reproduce and contribute to overpopulation. Many animals have been shown to have homosexual tendencies, so the religious argument of it not being "natural" is not valid. The same thing about 'protecting the sanctity of marriage' and 'unnaturalness' was said in the 1960's about Interracial marriage, and yet this is (apart from a few select racist groups) accepted in society today. But opposing Gay marriage makes a fair amount of dollars for those using the issue to fatten their right-wing warchests.
Traditional Roman Catholics
The Roman Catholic Church condemns homosexuality in public but privately it happens. The Catholic priesthood is particularly vulnerable because preventing priests marrying greatly reduces the number of Heterosexuals willing to become priests.
[ Carmello Abbate undercover investigator] caught the priests [high ranking Vatican insiders] on hidden camera dirty dancing at private parties and engaging in sex acts with male escorts on church property. He also caught them emerging from dark bedrooms just in time to celebrate mass. In one postcoital scene, a priest parades around seminaked, wearing only his clerical vestments. “This is not about homosexuality,” Abbate told The Daily Beast when he published the exposé. “This is about private vices and public virtues. This is about serious hypocrisy in the Catholic Church.”
Other Newspapers also published this.
Further gay men have opportunities to join the priesthood.
Any American Catholic official well placed enough to know the facts would quite likely admit that there have been seminaries in the U.S. that were largely run by homosexuals and which were networked with the broader gay community to attract novitiates. 
Protestants and Anglicans vary in their attitude to same sex attraction. The fundamentalists and the Religious Right are at least as homophobic as traditional Roman Catholics, some like Fred Phelps are more extreme than RC's. Still Liberal Christians generally accept gays.
Churches that accept gays aren't hypocritical over this and are called Open and affirming, reconciling or other code words. Not all Roman Catholics are Homophobic, New Ways Ministry round Maryland got into trouble with the Vatican because they are LGBT accepting.
"Gay" as offensive
Since some of society does not really accept homosexuals, one of the things that holds progress back the most are words used as insults that relate to gays. In youth especially (around ages 11-15), use of the word "gay" as a term to indicate something or someone is bad in some way, is used very often. Again in youth the word "lesbian" is used in excess to show you are not one. If your friend does something that you, in your homophobia, might consider to be homosexual behaviour, you call her a lesbian.
Conservative lies about homosexuality
- Main article: Conservapedia and gays
Conservapedia has multiple long articles on how bad gays and lesbians are, to simulate the eternity in Hell they wrongfully believe gays will go to.
Conservative abuse of gays
Most conservatives enjoying degrading innocent gays by throwing things (books, chairs, holy water) at them or calling them "faggots" (and not only during rough sex play), because as we can see from the scandals in the Republican party, they are repressed. And repressed cardinals do it too. 
Anti-Gay societies are being created by conservatives who feel that homosexuals are just choosing to be annoying and should be taught to change. Closet gays may join these societies and look for other men like themselves there, now that risks HIV.
Can gay people change?
Really, someone should ask them, don't you think if homosexuals could change, they would? Why would you put up with all of the stupid, homophobic comments that come with your sexuality, with being rejected from society, resented by your friends? Of course, you wouldn't! If you had a choice or a real reason to change. Neither has presented itself to homosexuals.
There are too many stories of people desperate to become heterosexual who can't. Furthermore, there are too many stories of people who say they've changed but later realise the change wasn't complete or get caught doing something with their own sex that they wouldn't admit openly. Some Bisexuals probably have a choice whether they express the gay side of their nature, the straight side or both. Despite this many people appear to have no choice.
People who claim that they can make one "straight" sometimes are lying to get money from those they pretend to help though they subject themselves to further ridicule and discrimination of a scale that's worse than before if they're found out.
Furthermore, we can't prove definitively that all those who have claimed to have become "straight" have continued to have "secret sex" with persons of their own gender. They just may have been caught that way.
Matt Barber and his masculine Concerned Women for America
A "notable figure in regards to opposing the homosexual "agenda' is a guy called Matt Barber, who is head of Concerned Women for America  (sounds gay to me) says this: "Throughout society, homosexual activists demand that homosexual behaviors not only be “tolerated,” but celebrated. (That’s what the euphemistic slogan “celebrate diversity” supposes). They have masked their true political agenda by hijacking the language of the genuine civil rights movement and through the crafty and disingenuous rhetoric of “tolerance” and “diversity.”
This guy is a prime example of a complete homophobic moron. Sorry to be predictable - but true. He calls Homosexuals "activists" because he holds them in the same esteem as terrorists. "Political Agenda"? This agenda is evil because it includes points such as: Talk about homosexuals and homosexuality as loudly and often as possible, Portray homosexuals as victims, not aggressive challengers.. Give homosexual protectors a “just” cause. This agenda scares conservatives, as it has aims that would make life for homosexuals far easier and more accepted. Now that guy and others like him look like hypocrites since Bible Belt type Christians also regularly make problems for others and like to make themselves look like victims.
There may be genes that predispose men, perhaps also women to be gay. Research is actively being done but the results are so far inconclusive. It should be questioned whether discovering such a gene is actually desirable as conservative opposition to "playing God" is likely to fly straight out of the nearest window as soon as it is. It appears the environment has an effect as well. It is known, however, that homosexuals are not the Borg and do not convert people into homosexuals. 
- Gay marriage
- God Hates Fags
- Don't Ask, Don't Tell
- Homosexuality as a natural population control
- Harm the ex-gay movement causes
- Sodom and Gomorrah
- Was Jesus Gay Funny video
- The Biological basis of sexual orientation
- LGBT-welcoming church programs
- Wild and gay- Homosexuality in the animal world
- Wild Animal Gay Sex They look like dogs to me but they certainly like it.
- Did a Cross-Dressing Priest Sex Ring Bring Down Benedict XVI?
- Pope Benedict XVI Resigned Partly Because Of Powerful Vatican Gay Lobby, Italian Paper Claims
- Pope Francis and the Vatican’s ‘Gay Lobby’
- Catholic Cardinal Calls Gays 'Faggots' During Interview About Openly Gay U.S. Ambassador Nominee (VIDEO)
- The Genetics of HomosexualityThis is a very long paper that I didn't have time to read.
- How homosexuality is 'inherited' This seems to summarize the long paper.