RJ Moore,

If they offer to marry anyone then they must be compelled to marry everyone who asks

Even satanists?!

Yes, even them. If you offer a service to the public you must offer it equally to all. A shopkeeper or employer isn't allowed to refuse satanists business, or blacks, or gays, or women. Why should a church be any different? Just because you don't like someone that's not a good enough reason to have a legal right to discriminate against them.

All you're doing is removing the liberty of people to form voluntary groups free from state interference. If a church wants to admit only red-haired, left-handed vegans...what's that got to do with the state?

If the church is providing commercial services then it has everything to do with the state. A shopkeeper might want to serve only red-haired, left-handed vegan customers, but he doesn't have the right to do that. That's what anti-discrimination laws are all about, and they're necessary to ensure fairness and equality of opportunity. That's why we HAVE states in the first place - to place checks on the unfairnesses, inequalities and harm caused by the law of the jungle and rampant inconsiderate self-interest.

If all the church did was hold private meetings of friends then it would not be subject to anti-discrimination laws, just as the shopkeeper wouldn't if he was only conducting a private transaction with a friend rather than offering his goods for sale. But this is not the case. Churches are businesses, with incomes, products and turnover. They charge money for marriage services and conduct them as a commercial transaction (and, in most cases, as a legal instrument of state also).

They do not have the liberty to murder who they want, steal what they want, rape who they want or set what they want on fire.

Of course they don't, since such actions violate the rights of others.

Refusing marriage services to gay people violates their right to being treated equally and their right to be free from harmful discrimination.

What you seem to be suggesting is that groups of people who voluntarily come together should have to acquiesce, faced with the threat of state coercion no less, to the wishes of those outside the group, a blatant infringement of the members' liberty.

When the matter at stake is the fundamental equality of all human beings, damn right that's what I'm suggesting. Individual freedom to cause harm cannot trump universal equality. They're not at liberty to murder who they like, they shouldn't be at liberty to discriminate against who they like in the provision of services to the public. Because this isn't just a group of friends meeting in each other's living room - it's a commercial business that provides services to the public - marriage services. The florist isn't allowed to discriminate, the photographer isn't allowed to discriminate, the venue for the reception isn't allowed to discriminate. Why should this one service provider be permitted to discriminate on spurious and irrelevant grounds where none of the others can?

Also, would you extend your same concern for "liberty" to a church or shop that refused to provide its services to black customers?