All of the arguments I see against gay marriage are about either God or Nature. the God argument is that marriage is a religious institution and Homosexuality is a sin and, therefore, same sex marriages are against the Christian teachings. Very well, but what about marriages performed under different religions? Say a Pagan handfasting, for example? If that religion has no problem with it, should they be banned from performing them as well?
The other argument, the Nature argument, states that same-sex marriage is wrong because two men, or two women, can not have a child. This raises some serious questions with me. This goes under the assumption that the only reason people get married is to have children. Does that mean that the elderly can not get married? what about infertile couples? Are their marriages void now? There are a plethora of people who get married for an indeterminable amount of varying reasons. Many of them don't even have children, or choose to adopt. That invariably will raise the argument that children do better with Heterosexual Parents, or that having gay parents will make you gay. firstly, let me ask, am I straight because my parents were straight? the answer is obviously no, seeing as I am not straight; and secondly, even if you ignore the insurmountable amount of evidence that proves that children of same-sex couples do just as well, if not better, than their Nuclear family couterparts.
In conclusion, both arguments against gay marriage, have just been proven to be void. If you define marriage as a religious institution, then so be it, but why try and impress your views onto other religious institutions. And if your argument is that same-sex couples can not have children, are marriages between old and infertile couples void as well?