Jesus also never specifically said "don't sleep with your brother or your mother", but it's still wrong, immoral and illegal to boot.
What Jesus DID talk about was sexual immorality. Some Christians believe that homosexuality falls under sexual immorality.
Interesting that you say that, having brought up Sodom and Gomorrah, a story that continues with his daughters getting their father drunk, and getting pregnant by him. And those were the people looking for the "good people."
If one believes that homosexuality falls under immorality, then do they believe that all forms of heterosexuality are moral? Heterosexual child molestation, rape, prostitution, strippers doing lap dances? That exist, and there aren't thread after thread about that.
There are moral and immoral forms of heterosexuality, namely, those that are loving to the other, as opposed to those that harm the other, demean the other, or are selfish and unloving to the other.
The same can be said of homosexual acts, even homosexual acts committed by straight people (like prison rape).
However, there are loving heterosexual acts and relationships, and loving homosexual relationships that are edifying, nurturing, supportive and caring.
I have a hard time believing that is sinful.
Is it a sin to sleep with your mother? Well, I would suggest watching the episode of the X Files called House, where the The mother has three sons, one whom was the father and brother of the other two. What happens? Well, because the DNA is so close, people become deformed.
But how would a son marry his mother if he has a father?
Is it immoral and illegal if the father is gone? It's something that grosses most of us out, but probably has happened before, even in Shakespeare.
Do brothers and sisters marry? Rarely. Who would want to. The DNA problem arises again. However, when people talk of "God's Plan" of one man and one woman, A&E can have children, but the next generation
has to reproduce through incest. When you think about it, it's kind of icky, but that was their only option, and apparently, God's well thought out plan.
The only real reason that it is illegal is because of genetic problems in offspring. Legally, they are next of kin, and can share property rights, make life and death decisions for one another, without marrying at all. Were there a Mother-Son Pride Parade each year, this would be an issue, or a Brother-Sister Love Group calling for legal incestuous marriage, again, this would be something to debate and discuss.
However, there isn't. It is extremely rare that you hear about it, and not because it is illegal, but because most people are not in love with their brother/sister/mother/father past the age of 5.
Again, you can't compare such things as incest to homosexuality, unless you want me to say that a man marrying a woman is no different than a brother marrying his mother or sister, because it is heterosexual.
Surely you understand the difference.