The problem is with an over abundance of Classes in the last editions of D&D.
Whereas at the beginning there were only four (Fighter, Wizard, Cleric and Rogue) each of them with unique abilities (let's pretend to forget dwarves, elves and halflings) and eventually other subclasses of the main...
In the 1st edition, or BECMI, at a certain level Clerics could choose to remain such or to become Druids (Neutral alignment) while Fighters could choose between Paladins (Legal alignment), Knights (Neutral alignment) or Avengers (Chaotic alignment) .
Clearly Paladins were more familiar with...