NC made the point earlier that we shouldn't automatically respect another's beliefs. Personally I think that's correct. We ought perhaps to respect their right to hold them, however illogical they may seem to us. Of course not respecting a belief is not the same as disrespecting it.
If I simply hold a set of beliefs and don't want to test them, as far as I can see that's perfectly fair, however unwise others may think it to be. I may have good personal or psychological reasons for not wanting to challenge my beliefs at this point. The problem arises perhaps when I share these beliefs with others. If I share my beliefs in a place where I know I am in the company of others, for example a church, who profess the same beliefs, I think it is reasonable to expect that these beliefs probably will not be challenged, at least publicly, provided they conform to the beliefs of the church.
This forum however isn't the same kind of place as a church. Surely it is reasonable, if I express a belief, to expect others to ask why I believe it? This isn't a noticeboard so if I express a belief, probably discussion will result and I may learn that the basis of my belief isn't as sound as I thought. Isn't this simply the process of developing our own thinking? I am pretty sure most posters would agree this is obvious.
Offering an unsolicited opinion on another's beliefs in some places might be seen as rude, however by expressing a belief here it seems to me one is inviting the opinion of others.
it occurs to me that sometimes posters are not used to having their opinions or beliefs questioned or challenged. This can be a shock to the system, I know it was when my own opinions were challenged for the first time a long while back in the mists of my youth. Sometimes this is perceived as an attack, either because the person expressing the belief is unused to challenge, or is sensitive or because the person challenging them is dogmatic, aggressive or simply in command of more actual facts about the situation on which they have formed their own opinion. In this situation it is easy to respond defensively, even if that wasn't the posters's intention provoke it. Before long someone makes a personal remark and it descends into a chimps' tea party and opportunities to learn and revise our own opinions can disappear (not that I am against a verbal punch-up when all parties are up for it).
It seems to me that the key to understanding challenges (and also initial posts) is in part at least, down to understanding the motive behind them. I sometimes ask myself am I challenging someone else's belief because I really want to help the person develop, or because I want to reinforce or simply to test my own 'beliefs' or understanding of the facts, or because it makes me feel good, or simply to correct the record, or because I get some kind of gratification out of having an argument? (there are I am sure plenty of other motives too!). Understanding our own motives can be tricky (at least I often find it tricky).
I visit a few forums and I don't think the posters here are much different from a cross-section of members on other boards where discussion is encouraged. Perhaps some of us need to be a little more sensitive to the feelings of others and how we phrase our challenges and others need to be a bit less sensitive about being asked to explain themselves and why they believe they things the do in the face of information to the contrary.
Sorry this went on a bit. Just my two penn'orth.