I think they are tied to a church and take orders from the ones in charge of it. Protecting members, striking down enemies, basically knights just tied to their religion instead of someone like the king
The noun paladin means a champion of a cause. ... While the French word paladin means warrior, it was used specifically starting in the late 1500s to mean "one of the 12 knights in attendance on Charlemagne." As time went on, its meaning grew to include any chivalrous or heroic person.
So what's a paladin ?