when i say this, at least, i am making a distinction between (1) "we should take steps to stop people who are hurting others from being able to hurt others" and (2) "people who do bad things should have bad things done to them".
examples of (1): i hit my children, and am no longer allowed to see them. i use a racial slur at work to a coworker, and am fired. <- these things might feel like punishments to me, because i want to see my children / i want to work so i have money, but the focus in doing them is not to punish me, but to keep the other people safe - i can no longer abuse my children or my coworker.
examples of (2): i hit my children, and so i get publicly beaten in return. i use a racial slur at work to a coworker, and am put in solitary confinement for five days. <- these are punishments. they do not materially make anyone i have hurt safer (i can still see my children; i can still go to work with my coworker), because the assumption that people won't do something if they know they'll get hurt for it is simply not true (we have a lot of good evidence that hurting people doesn't make them change their behaviour, other than trying harder not to get caught).
of course, there's the option to do (1) and (2). i could be banned from seeing my kids, and also publicly beaten, but... why? why do we need (2), if we are already doing (1)? what does (2) do to materially make my children (or other children, for that matter, or anyone) safer?
and that's what "don't trust people who want to punish" is getting at, because the urge to punish is often really strong - especially in christian, especially evangelical christian, spaces, where there's this internalised "if you sin you go to hell" logic. people get hurt, and then they often turn around and say "well the person who hurt me should be hurt too", rather than "i don't want this person to be able to hurt me or others any more".
the problem with that is that like... well then we just end up in a cycle of hurting people for hurting others, which has negative consequences for everyone involved. as opposed to consequences happening that make everyone safer, and then rehabilitation efforts to stop people being hurt/doing hurting again. and it's also the same problem as the eternal "well it's okay to do X to Y group" (e.g. it's okay to remove voting rights from felons) - you are then motivated to turn anyone you want to do X to into a member of Y group (e.g. mass criminalisation (felonisation?) of black people via racially-selective policing and lawmaking). you start being led by "i want to do X to Y" as a knee-jerk response, rather than "what do we need to do to keep people safe?". violence becomes acceptable as long as it's for the Right Reasons.
tl;dr "punishment" and "your actions having consequences that you do not enjoy" do not mean the same thing here; there's a difference in the motivation of the person doing the punishing/consequences, and this quote-thing is arguing that that's important.
footnotes to this below the cut (bc they got longer than the actual post):
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