Every Man's Sword doesn't prevent battle challenges (Anymore), It's acutally even more worthless than Strength in Weakness (Ok, maybe not) It's errata says this:
"Protect each player without a Lost Soul in territory from being attacked."
So, even if you only have the N.T. and I've only got O.T. heroes, or if all your souls are in sites, and I don't have access, I can still attack you.