So you think religion is a load of bollocks, that's not controversial. What it is is your view, and you're allowed to have one, and any decent person will respect your right to have that view no matter how much you disagree with it.
The song seems a bit forward though. I don't mean 'it's too blunt and aggressive and it will offend people', I am actually just plainly critiquing the writing. There's not a whole lot of subtlety in it, which is often a good thing if you're singing/writing about a fairly contentious topic. The other avenue is to go balls-out aggressive (like Punk does), but I don't think that's what you're going for anyway, but if it is then you're not quite there.
In other words, you're going middle-of-the-road in terms of delivery and it doesn't really suit the subject IMO.