"The paladin has a number of very powerful aids in his continual seeking for good: He can "lay on his hands" to cure wounds or diseases in others... They have a 10% higher saving throw against all forms of attack (excluding melee) ... [They] dispel evil ... and they detect all evil..."The paladin's purpose is to do good deeds and oppose evil, and for that purpose, the paladin is able to heal others (not themselves) and can find, resist, and drive away evil.
What is the paladin's code? Contrary to the popular interpretation, I don't think a "roll your own" approach is appropriate. It's supposed to be "do good and uphold what is right." Paladins sacrifice themselves for others. Or, a simpler, more enforceable version: In any situation, a paladin's priorities should be:
- The innocent and helpless;
- Their comrades;
- Their opponents;
This is meant to work like Asimov's Laws of Robotics: if you could save your friends, but you think about your own safety first and try to save them from a distance, you are not a paladin. If a damsel cries out for help, but you decide to help pack up camp first, you are not a paladin.