Had Stephen voiced these thoughts about Matthew's dichotomy of beliefs, Matthew might have responded with an obvious joke, that he would not have really meant as a joke at all: namely, that Catholics ate Death (or at least, the dead Body of Christ) at the close of every Mass-- the Eucharist.
As it was, however, he only responded to what Stephen had said aloud. "Really, I'm fine, Stephen! Well-- I'm fine now at any rate! I mean, I offered to make us both tea, completely forgetting that I had given it up for Lent! Coffee, as well, really -- no stimulants for me at all! I mean, I thought it would help me sleep better -- but such was... not really the case!" He grimaced again, apologetically, as he added, "Di died on the Friday before Advent began, last year... And... well... the Lenten season, so similar to Advent, has reminded me of how much I miss her...!"
He grimaced yet again at the mention of Bellatrix Lestrange's priorities. "Well -- she does enjoy hunting the 'wandless, powerless Mudblood rats'! I mean, it gets her conviction rates up; particularly so when she can keep them alive long enough to throw to the Dementors to finish them off...!"
He looked blankly up at Stephen at this last, his face as unreadable as his Death Eater's mask. "Subvert the regime? Stephen, are you mad?! I'm but one man, against DOZENS of bloodthirsty bastards -- pardon my French!" he added, ironically, knowing full well that the profanity he had used was indeed of French origin. "Yes, Stephen, it is that bad for me...! I mean, I miss my sister so damned much -- and it was my Lord who killed her!"