Thanos, due to the fact that the data gathered so far left him mostly confused and perplexed, ventures forth, seeking to somehow learn more of the current power balance within the ranks of the clergy, perhaps he may stumble upon conflicting interests and similar.
Weakening the bond pushing the clergy of the old to band up under the banner of preserving the order based on an illusions… can only be defeated with the use of the old and tried pattern - divide and conquer.
What sort of wedge one could use to separate the preservers of the old customs ?
With such in mind he seeks to simply make use of his way with words, posing as a foreign scholar (whom he is, partway) seeking to learn more about the history of the city and the church of the 'Old Pharaoh'.
He expects to find few distinct views on the matter, still within the doctrine of the cult of the old Pharoh. Sects ? Perhaps simply factions ?
Where there's diversification the order crumbles without strong leadership, strong leadership which is fading as the very top of the hierarchy seeks to embrace the change.
"That's us, defeating evil by being even bigger bastards" - Baltasar Malich commenting the latests exploits of "The Evil Trio" (himself + Altharid and Sidhe Spellweaver)