This is impossible. Marriage is a religious act, it always has been. The problem is that marriage is mixed into the law. If the law was completely seperate from marriage and a contract such as civil union was given to all two parties who want to marry, straight or gay, it could be possible to talk about marriage without bringing in religion. But as it is, marriage is a religious act and the religious should have the right to limit who marries--- as long as the government does not endorse marriage or give it any legal merit. If it's part of the government, automatically a church has no right to dictate the law.