Try this one on for size.
If the gay marriage is performed at a church then it is a religious ceremony. In that case the baker is being forced to participate in a religious ceremony. That means, the state is establishing a religion and forcing everyone to participate.
If the gay marriage is performed at a church then it is a religious ceremony. In that case the baker is being forced to participate in a religious ceremony. That means, the state is establishing a religion and forcing everyone to participate.