The man is blatantly identifiable as a convention delegate, he walks the exact path to and from the center, likely collecting his stipend each time.  Thea can't blame him, the stipend is good money, and, under some moderately optimistic scenarios about the Queen's intent for the convention, easy money.

The place he's walking from is more interesting, a temple of Erastil.  Perhaps one of the delegates of his faith?  Or a simply a faithful chosen by election or sortition?  Either way, he has some connection to Erastil, and will hopefully be amiable to Thea's idea?

She games out various scenarios with Dia and her other students: if the man is almost completely ignorant of Erastil, if the man has some bizarre theological take he is fixated on, if the man has good theology but a few blatantly odd beliefs mixed in, if the man has some convention term he is already set on, if the man has bad experience with schools, if the man opposes the concept of education itself (this one actually seems to be an unsolvable dead end).

Meanwhile, she has another student make a cheap copy of her worn and burnt copy of the Parables of Erastil.  She intends to give him the original as a gift... but after considering what little she has learned of Erastil from his parables, it occurs to her one of his clerics might prefer a more practical gift.  So she has another copy made, this one with a bit nicer binding and a water resistant bag to go in.  And then a student asks what if he can't read.  (She couldn't have had that idea a few days earlier?)  So... Thea decides that if he can't read and has no one to read it to him but accepts the gift, she will send a student every day to read a chapter from it to him.  And they have one last idea before she goes, the Parables of Erastil often have a few unique chapters with fables based on local events or traditions, so they come up with parables of their own, vote on their favorite, and add the best one to the end (clearly labeled as additions from the Abbey of Ashes for whoever of Erastil's may read them). 

So, some time after one of her students first noticed the man, Thea arrives at the temple, book in bag and bag over her shoulder, just as the man is on his way back.

"Greetings, I'm Thea, monk and cleric of Irori and delegate of his faith to the upcoming constitutional convention.  Are you a delegate?  If so, would you be willing to take some time to talk about it with me?