If you're secure in what you believe, there's nothing that can really offend you.
I came across that comment on a message board recently, and it reminded me that one of the traits that separates fundamentalists (and obnoxious ideologues of all stripes) from mature believers (again of any stripe) is a driving need to convert everybody to one's opinions and beliefs.
Not that one has to abandon the concept of evangelism if that's an important component of one's faith, but evangelism can be conducted without the issuing of ultimatums - and even without the use of words at all. The most persuasive examples are those individuals who place the most demands on themselves and the fewest on others.
If I'm truly confident in my beliefs, it isn't going to shake me if nobody ever converts to my way of seeing things; that's God's job, not mine. I'll no doubt still celebrate such a conversion should it happen, but in the meantime my job is to love others and accept them as the bearers of God's image that they are, regardless of their beliefs.
The insecure believer fears disagreement and feels threatened by those who see the world differently. They may hide their fears behind 'biblical' pronouncements of fire and brimstone, but it's ultimately little more than a mask. To the immature, the outside world is a realm of darkness filled with traps and enemies, and those who cannot be converted must either be avoided at all cost or eradicated.
The secure believer is free to acknowledge and build on the common ground that can be found between any two people and to develop life-affirming relationships that the fundamentalist can only turn away from in fear. Differing worldviews provide opportunities for learning, not for proving one's superiority.