I don't see why, using suicide bombers while tasteful to our RL morals and sad in quest seems like something to chat with GT about before assuming it will be seen negatively since this is same guy who turned a troubled young women into a holy weapon after all.
What're you going to do if he's all for it though?
Anyway, maybe this particular Grand Theogonist isn't the best source or advice for morality. Given that Evangeline apparently has a beef over him due to that, and Evangeline herself seems like a pretty good and just person and is seen as pretty good and just, maybe she's on to something about that.
I mean, there hasn't been much but hints and suggestions about what the whole thing with Regina and what the GT is trying and testing is, but it sounds shifty or morally dubious or disturbing at best, in some way.
As for why to do penance, or why to feel bad, or be disturbed, or try to make amends, or try to alleviate or affect public perception after the war or etc?
It could also be because Frederick himself feels bad about enabling and providing backing to suicidal fanatics. That, when he looks at Flagellants, he'd rather be thinking "What a waste" or "How could I help them? Or, how could I prevent more Flagellants happening?" rather than thinking thoughts like "How can I make their suicides more effective?"
I feel like there is a strong line between looking at war and going "These are how I will move some of my troops, and how I will try to best spend their lives accomplishing these objectives and keeping us safe", versus looking at... frankly, non-military troops but rather just the broken down and insane and fanatics, who just happen to blob up into mobs and wander over into battlefields.
I feel like people who wage war, and think about how best not to waste their troops lives, how best to spend them... still come from a place of, well, caring? It's not just about numbers and tactics and strategies for them; even if they work with numbers and tactics and deploy tactics and numbers. That's just the sort of person that, well, that people are. They care. They approach war in a certain way.
Some people are different and don't care as much. Some people are paranoid. Some people are control freaks. And all that gets put into the history and traditions of a province or military or knightly order. But.
All of that gets put in and remembered. Those people get remembered as good or bad, callous or caring. And people pass judgment on all that. (Or it gets warped in how it is remembered, and people take up more callous methods and think that's just normal or how things ought to be, or so on.)
Anyway. If you're doing something that you are disturbed by, and if you're taking desperate measures in desperate situation, maybe it's also reasonable to -- after it is all over -- to go "Man, I hate that that happened and that I did that, and I feel like I should maybe do something about that? About what I did and how I felt about that."
Some people don't care and are just taking the track of "Well, this is just a more efficient usage of Flagellants, no big deal." Others are more disturbed by the idea. Either because of external morals, or because of in-universe reactions and context (i.e. how Freddy and Natasha and everybody reacted), or so on. Other people are more ambivalent. Or hold other opinions. Or no real strong opinion one way or another.
We must give up drinking for a year. all show now of our sins and how heavy they weigh on us.
That... might actually count as a good sacrifice for Frederick? For somebody who is as heavy a drinker, by Ostland standards even, as he is. (And who also has access to the best alcohols too, so it's not just somebody who drinks a lot of whatever is at hand.)
But there's also sacrifice of destruction. Sigmar loves it when you sacrifice lots of orc heads to him by destroying them. Or do a Quest for Sigmar.
Huh. Well, there's a hell of a lot of Druchii -- and Beastmen -- that we will be able to sacrifice to Sigmar. Would that count, would that help?
Or do a Quest for Sigmar.
... A quest for Sigmar?
Is that a thing?
What exactly does that entail? Sigmar does/gives quests? Can you elaborate more, torroar? (Or was this just an offhanded mention and one-line thing, rather than signifying anything bigger or more culturally/religiously relevant?)
One of the career exits for the Flagellant career path was Priest, so maybe all that crazy wasn't so crazy, and it turns out they really can call upon the Divine Lore and bring down burning holy comets onto the heads of their enemies, and things like that.
Aha, I thought I had remembered that the Flagellant career had an exit path! ((Mostly via remembering somebody making a build or discussing a build, and mentioning that the Flagellant career can be a way to get immunity to psychology or to fear or to... something, it was something. I think that that implied that that was a pretty fucked up career. Maybe the sewer jack Skaven-hunter careers sometimes got them too? In which case, that just went how bad those experiences can be.))