On this question Is it possible to be a Christian by birth? I see that
User14 is greyed out. I have seen another users greyed out like that on one of my questions.
Were they deleted/banned? If yes, what did they do wrong?
Those users have been deleted. The ones you see have all been done at the request of the user, they are not bans or censorship! This sometimes happens when a user decides to quit using the site for whatever reason and wants their name un-associated from their posts.
There are a few users that we have deleted as moderators, but these are spam users for which we will also have deleted their content so you won't see them floating around the site.
If memory serves me User14 was a pastor who decided his time on the site conflicted with his other duties. While we disagreed on some issues, I very much appreciated his knowledgeable input and would have liked to see continue.
As moderators, we don't exactly "ban" users. We can and do sometimes temporarily suspend them if need arises. This action temporarily sets their rep to 1 and disables their ability to post/vote/etc. However their profiles remain viable and a notice on their profile page gives a general reason for the suspension and the date that it will be re-instated. The exact reason for their offense might not be made public, but the action taken would be transparent to the community.