After this episode I just couldn't stop thinking why father Brown is so out of character. I almost had to quit the whole series because he was so out of character based on what was established on earlier episodes. This could have been a good place for character growth for Brown, but unfortunately writers just handwaved all the painful questions.
The victim of the week was excellent, as everyone had a reason to hate them, and so a reason to kill them. Unfortunately the opportunity was wasted and the killer came kind of out of the blue, and so feels superimposed and artificial.
As whole, the episode is somewhat disjointed. Titular character is very much out of character especially at the end. Sometimes that can show viewers new sides of characters, but in this case it makes the Brown just look like weather vane, whose moral compass points to easiest solution. Also Sullivan's last comment about the murderer is stupid. And it seems like a cop-out from writers, who are too afraid to say the murderer will face the gallows.
Unfortunately this is one of the weakest episodes. Mostly because of poor writing, which tries to criticize the historical wrong doings of catholic church, but does it half-assed, and also mistreats the main character.
I want to like this episode, but I cannot, because of poor writing.