"The heretic called out to his captor, tha paladin, and insulted his faith and threatened death and dismemberment to his loved ones (something about having powerful friends)."
"You're a SOB! Your mother had every man of the kingdom between her legs! Your god is a FAKE! He eats right out of my dog's bung hole! Your entire faith is horse crap! When i'm free of my bounds, i'll get you. Oh, how i'll get you. And don't worry, i
will get away. I have powerful friends, you know. I'll tie you up and torture you for days. You'll beg for mercy, but you'll get none from me. I'll leave you for a couple of hours in a dark, damp cell while you cry in desperation and agony, only to return with your kid sister. I'll make you watch while i..." (And so on.)
Do we agree on the approximate content of what such a person is likely to be saying?
Is that worth killing him? People who are whackos and say that kind of thing abound, by the way. Even nowadays.
If the paladin was out to exact vengeance or justice on this individual by executing him, he should have done it at the outset. If he decides to bring him back as a prisoner, i assume there is a reason. The thing that makes the paladin change his mind about killing him is this guy's threats/insults. Again, i don't think you kill someone for that. If you state that the paladin kills him because the guy is a murderer, i contest that: he would have killed him beforehand if that was the reason.
Also, I'd note that they fought an Encounter with this guy before he asked for quarter. Unless he was a Level X Solo he had friends / allies that could go toe-to-toe with adventurers for at least a few rounds.
Again, why not kill him right away? Why wait?
Also, the DM posted part of the information the PCs have been given about this criminal: "He has publicly and brutally put to death anyone who would dare refute his claims."
So he's a dangerous criminal (with dangerous allies) who has committed brutal, public murders against innocents who has merely had verbal disagreements with him. He has stated that more of his allies that escaped capture will dismember and murder the Paladin's loved ones.
I don't argue that the prisoner is a SOB himself. Just that losing your temper and killing someone because he insults or threatens you is overreacting. If you want to kill him at the outset, do it.
The Paladin executes the murderous criminal and makes a public example out of him - an act that presumably would intimidate those thinking of acting like him from doing so - including those "powerful friends" that were going to visit "death and dismemberment" to the Paladin's loved ones. He also eliminates the possibility that the criminal might be able to communicate with or be rescued by his allies during his march through various towns and his trial - eliminating any further chances to hatch such a plot.
He was sent to take care of the murderer. Why did he chose to bring him back as a prisoner if he wanted to kill him? Wait: killing and all that stuff didn't warrant to kill the criminal, but insulting and threatening the paladin, does? This is a case of the paladin putting his pride before anything else.
Excessive? Probably.
Irrational? Doesn't seem so.
Unreasonable? That's arguable.
Obviously argualbe, since we're arguing about it
I believe it is clearly excessive and unreasonable, as you may have surmised.
The actions certainly weren't works of mercy, but Good doesn't have to show boundless mercy in D&D. Lawful Good, in particular, tends to show less individual mercy because it puts more emphasis on the costs and benefits of such actions against their impact on society as a whole. A Good character might let a thief go in hopes of sincere repentance while a Lawful Good character might take his thieving hand because setting him back out upon the populace does a disservice to the innocent villagers and such.
I don't think that cutting out a hand is a good measure. It might be lawful neutral or lawful evil, but it's certainly not good.
"The end justifies the means". That is a lawful evil principle. It initially comes from Machiavel, thus the expression "machiavelic". If you are ready to exact vengeance in any way to uphold the law, you are acting in a lawful evil manner. If your ideals are so important that you wish them to be upheld by everyone, you'll conquer under the banner of those ideals, imposing them to all. That is lawful evil.
You appear to be supporting your arguments based on how law was upheld during the real-world dark ages, e.g. cutting out the hand of the robber, executing and torturing prisoners, etc... Although that gives an example of how harsh conditions were back then, we are far from what is lawful good:
(PHB p. 19):
If you’re lawful good, you respect the authority of personal codes of conduct, laws, and leaders, and you believe that those codes are the best way of achieving your ideals. Just authority promotes the well-being of its subjects and prevents them from harming one another. Lawful good characters believe just as strongly as good ones do in the value of life, and they put even more emphasis on the need for the powerful to protect the weak and lift up the downtrodden. The exemplars of the lawful good alignment are shining champions of what’s right, honorable, and true, risking or even sacrificing their lives to stop the spread of evil in the world.
I don't see honor in death through torture of one who was captured.
Bahamut, in particular, is not a deity with Mercy listed anywhere in his portfolio. In fact, the heavy burdens of Honor and Justice are often perceived to be quite merciless.
Lawful evil is merciless in the face of law. Lawful good is not. It is not because you defend justice that you defend it
at all costs.
At a quick glance, i do not see mercy listed in any god's description. However, i assume we'll agree that mercy is a trait that would fall under the good alignment, as far as alignments are defined in D&D - because we are talking about the game of D&D here where alignments are defined. Cutting a hand is not good, even if it was done by the law-enforcing men during the dark ages. (Why would you say that cutting hands of robbers is not done by western societies' justice systems anymore, by the way?)
Fun conversation by the way.
Sky