I'm not a Christian, but grew up learning the Christian bible in my younger pagan years.. Strangely, a lot other pagan friends I had where well versed in the bible and I spent a lot of time researching and reading it growing up with them. If you need some evidence for the condemnation of homosexuality in Christianity, just read the writings of Paul. Paul is one of the great Christian apostles and makes it pretty evident that sodomy is condemned. He also was condemning of the Greeks who practiced homosexual pedophilia in their culture.
Also, the book of Revelations talks about fornicators and dogs (which was a term used for homosexuals/pedophiles) do not go to heaven.
Christianity is an Abrahamic based religion and it follows many of the Torah moral laws very closely, just as any Abrahamic based religion. That would even include Islam, which follows Torah moral laws, although warps a good majority of the other Torah mitzvot in favor of Arabic pagan practices.