I think the first thing to do is break the link between "paladin" and "knight". It's the classic formulation, but that's because the original paladin's image is based on medieval knights fighting in the name of Christianity. But take an LG deity in your campaign setting, and try to build the paladin in his image.

You tagged your question Pathfinder, so I went over and checked the [Lawful Good gods][1] in Golarion, the default setting's pantheon. What do we have?

[Andoletta][2]
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>**Portfolio**: Consolation, Respect, Security<br/>
>**Description**:  appears and acts like an elderly family matriarch. She treats her flock as any grandmother would, protecting the innocent, reprimanding the wayward, and punishing the sinful.

How would a paladin of Andoletta be seen? A woman, probably. Not necessarily old (since you have to start somewhere) but compassionate. Perhaps a healer or wise-woman, who also steps in to defend her friends and charges when they are risked. She or he could be a member of a large extended family, even a noble family, and be the protector of the household and the family name.


[Erastil][3]
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>**Portfolio**: Farming, Hunting, Trade, Family
<br/>
>**Description**:  He is a god of the hunt and of farming, leading his followers by example and good deeds rather than flowery rhetoric

The classic paladin, the one we're trying to avoid, LIVES by his flowery rhetoric. A paladin of Erastil will seem to many to be a ranger. He might live in small farming communities, maybe even *outside* the communities, but he serves as their protector. He makes sure the traders coming in for the harvest are safe, that no shady dealings occur, and that monsters and animals don't hurt the town. Think of a classic wild-west sherriff, protecting his little town. That could be a paladin of Erastil.

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The list goes on, and you can think of many more archetypes. The Sherriff, as we said. An Exiled Prince, on a divine mission to reunite a torn kingdom, can also fit. What most of these archetypes share is that they're not necessarily *preachy*, and they're not necessarily dogmatic and rigid. Paladins are Lawful Good, but they don't have to be Lawful Stupid. And their Paladinhood doesn't have to be their only defining trait. Take any LG character, add divine motivation to their actions, and you have yourself a paladin.





  [1]: http://pathfinder.wikia.com/wiki/Category:Lawful_good_deities
  [2]: http://pathfinder.wikia.com/wiki/Andoletta
  [3]: http://pathfinder.wikia.com/wiki/Erastil