Board Thread:Oblivion/@comment-5371482-20130728024542/@comment-5215868-20160616045147

It's possible to retain the NPC's belief of you being a holy knight even if you complete the Dark Brotherhood and Theives Guild quests. You'll never get that line "I used to think you were a hero..." This is how:

Begin the quest for the relics, and acquire however many of the relics you like without getting them all. Next, do all the evil things you like, as long as you never accrue bounty for murder. (You can murder people, as long as you don't get a bounty, even if you are removed from a guild.) Be sure to pay S'kirvva or Armand to remove your bounty! Do not serve time in jail! Then, when you're done doing evil things, (finished DB and TG for example), walk the Pilgrim's Way again. Your infamy will return to 0, and if you have the Gray Cowl of Nocturnal, you can equip that to commit any further crimes without the increase of infamy.

NPC's will never know the difference.