[Vautrin]

My statement was not about comparing religions. But about the beliefs believers of various religions hold.

If you are going to condemn non-believers, because they do x,y or z, then the natural reaction of some non-believers to condemn them for practices a, b, or c, from their own scriptures.
And likewise, if a Muslim attacks a Christian, for not living up to Christian standards, a Christian can point out to the Muslim that he is not doing the same thing either (Muslim standards).

Of course, a believer does believe in her / his religion. But the moment it leads to lines like: "You live in sin." "You are evil." "You are a non-believer." I cannot see the tolerance and respect in that, and probably most people who are talked to like that, won't. Hence of course the retaliation.