I once played a Paladin who's code was based off of the virtues from Hunter: the Vigil.
A Paladin must be Merciful, for they are creatures of good. Feed the hungry, help the helpless, and never forget that you are a servant, not a master.
A Paladin must be Zealous, for evil does not simply go away. It is always there, waiting, watching, and preparing. So to much the Paladin watch, wait, and prepare, for when words fail, the blade must be drawn.
A Paladin must have Vision. The future is cloudy, but it can be prepared for. Evil will be prepared, therefore so must the Paladin. Know yourself, know your enemy, know history and philosophy so that you are prepared to fight them where-ever it may be.
To Lack Vision is to be lost. To Lack Zeal is to be dead. To Lack Mercy is to become that which you fight.
All things in balance, all things in accord.
Such is the code of the Paladin.