When I first read Sofie's words, the first thoughts in my head were dirty ones. I started imagining Ed being something like a cad, flirting with her in a sexually suggestive way. It occurred to me, then, that neither you nor Sofie would appreciate that. So I put the situation in a different perspective - strong man versus vulnerable woman, warranting pity. But if you marry for pity, the pity eventually wears off, leaving behind only contempt and disdain. So I tried yet another perspective, which initially eluded me, and which you'd actually made explicit: By accepting his offer, Sofie was putting her trust in Edward. That I would think dirty thoughts about such a thing disgusted me.

Given Ed's moral compass and background, it's highly likely that the same chain of thought went through his head as well. This is what his religion looks like, deep down. It's not the "easy crutch" that some people think it is. It's a death-battle, a vicious struggle between our carnal desires and our better judgment. I figured it would make for some effective character development. If you want to get to know someone, what better way to do that than to see the very thoughts in their head?

Besides, he won this time, but given his proximity to Sofie, it's possible he'll lose that battle next time and give in to temptation. He seems holier-than-thou this time, but give him time. His internal struggles only get worse from here.