Gnomon

Bogwater Tavern
If you try to talk to him while at level 3 or lower, he will reply:
 * Inquisitor Gnomon: The Silver Flame fights for the purity of Stormreach! While others of my order may tolerate Sovereign Host worship and similar ignorance, a true warrior of the Flame knows that such weakness undermines our citadel of righteousness. Truly, it is better to punish heretics than to convert them.

If you are at level 4 or higher, however, he will reply: Talking to him after acquiring the quest, but before completion, will make he say:
 * Inquisitor Gnomon: The inquisitor of the Silver Flame looks directly into your eyes. Are you a faithful servant of the Flame? Are you prepared to demonstrate your devotion with unquestioning service?
 * You: Yes, I am.
 * Inquisitor Gnomon: Good! These prissy Phiarlans refuse to obey my orders, but you seem... different. A small group of elven missionaries have built an underground chapel to the false gods of the Sovereign Host and hired halflings for protection. In the Silver Flame's name, I want them all removed. Taught a lesson. Exterminated, to put it bluntly. This holy work will lighten your spirit and fatten your purse. Will you purify the fools by fire?
 * You: Who am I to reject the will of the Silver Flame? (Bestow quest)
 * Inquisitor Gnomon: Exactly the right attitude, my child! The way to their vile chapel is not far from here. Go forth and ensure that the Silver Flame remains unchallenged in these blessed lands.
 * You: Not particularly, no. (Walk away)
 * Inquisitor Gnomon: Inquisitor Gnomon eyes you warily. Having second thoughts about purging the heretics from Stormreach? Others can be found for this work... but I will not forget that your allegiance was lacking.

On completion of quest, he will congratulate you with the following:
 * Inquisitor Gnomon: Inquisitor Gnomon smiles as you recount the bloody destruction of the hidden chapel. Yes... it sounds like we eradicated this cult just in time! As harmless as these Sovereign Host worshippers may seem, they draw believers away from the Flame, and that must not be tolerated. You have served me well.

After completing the quest and take the reward, if you talk to him again, he will reply:
 * Inquisitor Gnomon: Inquisitor Gnomon beams at you. Congratulations, again, on your staunch devotion to the Silver Flame. Some adventurers shrink from enforcing our faith at the point of the sword. But weakness and confusion will not serve us when we come face-to-face with true evil! You did only what needed to be done.

Lords of Dust
You met him at the entrance of the quest, alongside a novice priest.
 * Inquisitor Gnomon: ????????????????

After you dispatch all custists in the first room, he will say:
 * Inquisitor Gnomon: ????????????????

Further inside the quest, when you meet him again, you overhear a conversation he is taking with the cultists: At the final room, you meet him alongside Karas, the cult leader. He then gloats to you:
 * Inquisitor Gnomon: ????????????????

Then you finally fight him, in his true form: