Another swing and a miss from James. He's now falling back to the move of 'I bet these Christians aren't even motivated by religious belief. They probably just don't want to serve gays, but they're more than happy to serve divorcees and polygamists!'
I pointed out the problems with James' reasoning. First off, there is some kind of amazing irony in the fact that the self-described "progressive" Christian, who throws out large parts of the New Testament he dislikes or finds 'outdated', wants to enforce a religious litmus test to determine whether or not someone's religious beliefs are sincere. Keep in mind: James isn't offering to analyze the religious beliefs of the baker or photographer in question and see if their actions are consistent and sincere. Instead, James wants to use what *he* thinks Christians should believe if they're not "progressive" (he'd have to, since otherwise James himself would be marked as an insincere Christian immediately based on his own stances), and if they deviate from that, he'll judge them as insincere.
Beyond that, James' claims that a dislike of gays, rather than any sincere religious motivation, was behind their decisions not to provide a service for a gay wedding is subject to a much easier test: see if the service will be provided to gays individually, or for two heterosexual men marrying each other. This alone is enough to blow out of the water the suggestion that 'dislike of homosexuals' was operative in the service refusal - but this standard won't be adhered to precisely because it's realized that the service providers thus far in question, and likely quite many of them besides, would pass muster. And the goal here is not 'find a reasonable standard' but 'find a standard that results in people who disagree with gay marriage being bullied in every possible venue'.
Will having any of this pointed out to McGrath matter? Not insofar as his reasoning goes - because, as I've said in the past, reasoning and intellectual force of argument doesn't mean a whit here. What matters is McGrath feels a certain way, and "progressives" are chanting with a unified voice, and that's really enough to settle the matter. Point out flaws in their arguments and their reasoning, and you haven't provided a good argument - you're just a sneaky, hateful person who is using tricks like 'consistency' and 'discussion' to try and advance your wicked cause.
Progressivism sure seems a whole lot like tribalism for wannabe cultural elites.