Pfff. Damages from wars are relative, since they aren't permanent. Wouldn't be so hard to stuff down people's throat that it would be "better for civilization" on the long run. Plus that faith doesn't have everyone follow it either.
I'll believe it the day they come to D'Hara and Fissoa with a non-aggression pact proposal.
True, but the King of one Lurian realm is the prophet of the religion, thus you are left only facing a single realm, hardly able to force imperialism down anyone's throat. Besides the Dominant religion from LN is trying to expand into Fissoa, so they are hardly going to take kindly to a war against them.
