As is hopefully clear from the question http://meta.matheducators.stackexchange.com/questions/251/can-we-be-respectful, I flagged your comments as "Not Constructive". MadScientist's comment on that meta question sums up why I did so:
The huge problem is that one not-really-offensive but non-constructive comment is very likely to draw an at least borderline offensive comment from the opposing side, and then the cycle continues.
Let me address your points:
One was an explanation of why I downvoted the question. One was an explanation of a downvote I gave on an answer.
That was most certainly not made explicit in the comments. None of them started with "I'm downvoting this because ..." or even the shorthand "(-1) because ...". There was nothing in them to link the comment to the downvote. The comments did not make this any clearer since they did not address the actual question or the actual answer.
one can go overboard by creating the impression that contributing to the site is not valued just because the contribution may be a minority view.
This is one of the key differences between how it would seem you view SE sites and how I do. Comments are not contributions. Questions and Answers are contributions. Comments are there as a way of polishing the questions and answers. Long comment discussions are specifically discouraged. Now, this is frequently abused - I do so myself - but nevertheless, the goal of the SE network is to build up a resource of useful questions and answers, not as a forum for discussion.
I suppose that many theists believe that the use of a word like "spiritually" is sufficiently inclusive that everyone will feel like it's a warm, fuzzy, noncontroversial thing.
No, actually. I can't stand the word. However, that's irrelevant. My understanding from the question was that the word "spriritually" was handed down from "on high" (ie the University authorities). So attacking that word was definitely not constructive.
I don't think it's appropriate to allow discussion of how to use mathematics to promote a nonrational belief system, while deleting any attempts to protest that mathematics should not be prostituted to this purpose.
And here's the key. I completely agree with you. It is inappropriate to allow discussion of how to use mathematics to promote a nonrational belief system. Not that I consider my belief system to be nonrational, but that's by-the-by.
However, this question was not asking for such a discussion. It was "How do I fulfil this requirement?". Any discussion as to the reasonableness of that requirement is irrelevant because the requirement exists and is not going to go away.
Summing up, I felt that you had misunderstood the question and were leaving comments based on that misunderstanding which, in the context of the actual question, were non-constructive. So I flagged them.
I was not engaged in silencing anyone (see how easy it is to post something inflamatory? Jim's post is trying to be conciliatory but that last sentence riles me). I was engaged in ensuring that the focus of that page was on the specific question asked, and not on an irrelevant discussion which would not achieve anything other than to enrage people. I have engaged in such discussions on the internet before and not only do they not go anywhere, they also end up spoiling the place where they occur. I will happily debate the nature of mathematics and religion in a pub (or nearest equivalent) but not on the internet.