Claims like these are actually impossible to demonstrate or prove, but they are common nonetheless - perhaps for that very reason.(1) There is little question that fighting over homosexuality damages the members of society who are denied equal rights under the law and are treated as second-class citizens.(2) As for marriage, we don’t think any responsible observer would attribute our current problems with marriage in the US to LGBTQ persons. There is no situation where a societal ill can be legitimately laid at the feet of the LGBTQ community, where no other causes or circumstances can be identified. The above argument is rendered meaningless, and is simply an expression of fear, or perhaps frustration, deserving a pastoral response - but not validation.(3)
Furthermore, ‘traditional marriage’ is a recent social construct. Our contemporary romantic ideal was a terrifying innovation 100 years ago. Traditionally, marriage has involved polyandry, polygyny, surrogate pregnancy, concubinage, arranged marriages, marriage between children, and others.(4) The Bible approves of at least 8 types of marriage, including marrying war hostages, marrying slaves, marrying up to 700 women, marrying a sibling’s widow, marrying one’s rape victim, and others.(5) We rightly reject these many forms of ‘traditional’ marriage.
1. This argument, that homosexuality is damaging to society, is so common it is difficult to even begin citing it. This is amazing, given that there is no support for it whatsoever.
2. LGBTQ suicide rates, rates of substance abuse and depression, are often higher than that for heterosexuals. Opponents of equality for LGBTQ folks might say that this is due to despair of being trapped in "the gay lifestyle" (as if such a thing even existed). Recent attention has been drawn, however, to suicides due to the bullying of gay teens (or teens who are perceived to be gay).
3. Correlation does not imply causation. Just because some people perceive a decay in society does not mean that the decay is caused by a decrease in discrimination and abuse directed toward homosexuals.
4. Some of these still persist today, but for the most part, the industrialized idea of marriage is of two people who are societal equals marrying because they love each other and they choose to. This is a modern innovation in a lot of ways - not the least of which the idea that men and women are equals (something that one could easily find Biblical passages to refute, if one were so inclined).
5. Polygamous marriage, which was common throughout the ancient Near East, as well as elsewhere; Levirate marriage (Gen 38:6-10); a man marrying his 'property', a female slave (Gen 16:1-6, Gen 30:4-5); concubinage (Judges 19:1-30); a male warrior and a female prisoner of war (Deut 21:11-14); a male rapist and his victim (Deut 22:28-29); a male slave to a female slave without consent, and of course; monogamous marriage, which was often arranged marriage, and occurred between what we would now define as children. We need to note that in some of these cases, these forms of marriage were created as protection for women, such as women taken as 'spoils of war', or rape victims, or slaves whose masters force them to marry. We would now rightly see even the concept of taking a human being as 'spoils of war' as reprehensible, and we rightly reject slavery in all forms. We therefore reject as immoral these definitions of marriage even where the original intent was to protect against a worse possibility.