lol, so their oath is NOT to a diety, but to absolve their going against their oath, they need a diety.
5e Paladins seem really strange. It's as if they wanted to remove the religious requirement from them but realized that it was sort of at the core of being a Paladin and couldn't really take it all out.
Yes, completely agree, this seems to be one of the REALLY strange parts of 5e D&D.
The Paladin, along with the Ranger were the first "hybrid" classes that combined elements from two of the basic classes (Cleric/Wizard/Fighter/Thief). They appeared along with the Blackmoor and Greyhawk campaign settings ( 1970s ), long before Ed Greenwood was approached to collaborate on the Forgotten Realms.
The Paladin was based on the notion of religious orders ( like the Templars, Hospitallers or Teutonic Order ) mixed in with the medieval romantic fantasy stories surrounding the european dark age knights, including "The Knights of the Round Table" of Arthurian legend, and the "Counts Palatine" that were the Carolingian Emperor's equivalent of the Round Table, and from whom the Paladin name is derived.
From a mechanics viewpoint, the original Paladin was a D&D fighter, dedicated to a specific deity, from whom it received it's non-fighter powers, including Turning Undead, Cleric Spells, "Lay on Hands" healing, and receiving a magical war-horse. Neither the Cleric, nor the Paladin posessed or learned any "innate" magical powers ( unlike the Wizard ), but instead prayed to their deity to act as a conduit for that deity's power.
To the best of my recollection, the original Paladin could only be Lawful/Good in alignment, but no particular deity was specified; the L/G alignment would obviously limit the deities a Paladin could worship. I can't swear to it, but up to and including 3e my recollection is that the Paladin was little changed, and was definitely connected to a particular deity, because that was the source of their power, just as with clerics. In terms of the Forgotten Realms, Paladins usually worshipped Tyr, Torm or Helm; deities that allied with each other. It is likely that a Paladin of any of these gods would revere the others also, but their power came from a singular god they worshipped, and that power could be withdrawn if the Paladin misbehaved.
This obviously leaves a big hole where neutral, chaotic and evil deities don't have equivalent religious fighters. That was partly filled with an "anti-Paladin" class, called the Blackguard, for evil deities ( Neverwinter Nights featured Aribeth, a Paladin that fell from grace to become a Blackguard ), and I suspect there may have been other classes in 3e/3.5e, but that was after I stopped playing the TT game.
But the 5e Paladin seems to be an attempt to "rationalize" the religious warrior class by removing alignment...and possibly religion...which is definitely strange to me. The idea seems to be inspired by the oath-swearing warriors of the Celtic and Germanic dark-age tradition to de-emphasize the direct relatonship to a deity ( which is in itself odd, as these dark-age warriors typically invoked deities in their oaths).
But this then leaves the Paladin as having a "power source" that is simply the power of their conviction, which is somewhat meaningless in the context of D&D non-arcane magic, which is otherwise rooted firmly in deties ( including druidic deities ). To me. this is a particularly unsatisfying and botched class concept, but that is a WotC choice rather than Larian.
