The various principles are different because they align with the collective consciousness of the people they are addressing at that time, but when explored from a higher panorama, the higher principles are the same.
Can't be a true moral or ethical system if it does not incorporate the principle of justice at times when no one is watching.
While some special people can be moral without the need for reward or punishment, the generality of society seems to require reward and punishment as a means for practicing the more challenging moral patterns, such as honesty, truthfulness at all times, patience and humility.
