There seem to be some common themes in this thread:
1)Those that support the baker and see nothing wrong with what she did.
- Those that support the baker but would have liked her to have handled the situation differently, while still not backing down on.
- Those who do not support what the baker did, labeling her actions as “judging”. or otherwise discriminatory (in an arbitrary sense).
This, methinks, is a different situation than another merchant or service provider who may have customers or clients who are gay. She is creating something with her cakes, not just selling something off the rack. In effect, it is her “creative stamp of approval”, perhaps, that she is refusing to give to the customer’s gay “marriage”.
Different, methinks, than a tuxedo rental company who may rent tuxes for a “gay wedding”. Different than a food caterer who prepares food for the gathering (unless it is perhaps a private chef who has specially created a unique dish for the celebration). Different than the guy who rents out the hall for the celebration.
So, I think the comparison to other businesses is a bit of an apples and oranges comparison. I have several veterinary clients who, by all appearances, are in gay relationships. (The owners are the clients, the dogs, cats, etc, are the patients.

)
I don’t feel any differently towards these clients or do “business” with them any different than with my “straight” clients. However, I am not endorsing their relationships or behavior by treating, examinating, vaccinating, etc. their pets.
A good point made earlier in this thread was that this “wedding” is a very public acclaimation of this couples lifestyle and presumably ongoing homosexual activity. Participating in this acclaimation indirectly, as the baker woman would have been doing is not necessarily sinful, but her conscience certainly told her not to do so. On the other hand, another baker in the same situation might have his or her conscience tell them that while it was not necessarily a good idea, that making such a cake might not be sinful.
I think those that say that she in order to be consistant, she would have to ask about the pre-marital sexual activity of those with “hetero” cake orders go to far. Their sin, if it existed, could be confessed and removed. (So could that of the gay couple). However, the ongoing sham of a marital union and the ongoing homosexual activity is ongoing sin, which would seem to demonstrate a “married” gay couples intent to continue in sin. When the “hetero” couple gets married, it no longer continues to be sin. Big difference.
Very few businesses would seem to be involved in such a way as a baker of wedding cakes in a homosexual couples celebration of their sinful relationship.