This is assuming that “gays” are indeed born that way based on studies.
Science has
moved away from the idea that there’s a “gay gene”. It may still be possible gay people are “born that way”, since one non-genetic factor that is believed to play a role is hormone exposure in the womb. Obviously, that is still outside the person’s control, as are many environmental influences.
God only condemns homosexuals who engage in homosexual behaviour
Even then, it is less “homosexual behavior” and more that such intercourse is considered wrong under any circumstance. If a married man and woman commit sodomy with each other, it is just as wrong as if two men do it.
Why did God limit marriage between man and woman if some people are born with homosexual attraction?
In Genesis, God instituted marriage prior to the Fall. It predates any form of concupiscence.
But beyond that, marriage is effectively a physical reflection of two great spiritual relationships. First, there’s God Himself, wherein the love and union between Father and Son is so strong that the Holy Spirit proceeds from it, bringing about new life. Second, there’s Christ and the Church, where the two give themselves to the other, love the other, are unified with the other, and bring spiritual life into the world through their union.
If marriage is meant to reflect that,we know marriage is intended to be:
- Loving
- Unitive
- Procreating
Without getting into debates on the first two, gay couples are obviously incapable of the last one.
And as an extension, contraception, masturbation, sodomy (even among men and women), etc. are considered immoral due to similar reasoning.