We witness how draenei are turned into Lightforged. The Forge of Aeons reinforces a draenei’s mind, body, and soul with the power of the light after facing their inner demons and their inner turmoil
But this not means you are necesarily have to be “good”.
T’paartos faced his memories and fears, striking down physical manifestations of them. His Lightforged trial with him confronting T’paartos the Fallen, an image of his darkness who tempted him to leave the Light behind and embrace the Fel.
But a Lightforged Warlock (or Draenei) are not leaving the Light behind!
A Warlock - according the visual guide - are magical practitioners that seek to understand darker magics, among other fel-based and destructive spells. While many warlocks willingly follow the Burning Legion, there are those who work against it, using their magic to fight against evil.
Legion class preview even states, though they often pledge themselves to the service of noble causes and are not innately evil, their desire to understand darker magics and exercise unwavering command over demonic forces breeds mistrust among even their closest allies.
According the WoW game guide: In the face of demonic power, most heroes see death. Warlocks see only opportunity. Dominance is their aim, and they have found a path to it in the dark arts.
The ritual of Lightforging reinforces a draenei’s mind, body, and soul with the power of the light - so you are strong both mentally, spiritually and phisically. You have an extra layer of deffense of the Fel’s corrosive effect (you can sey, the Light already claimed you, and a jelous Force it is, guards what it have…)
During the trials you faced your inner demons, fears and weaknesses… and conquered them! Any weakness a Demon could exploit are gone! And you already - arguably - insane enough to be in a Cult. Yes. It is a cult mooooom.
The Light seeks one path and shuns all others as lies!
The Light seeks to rule, dominate, “guide” and uphold Order and Law and Justice - things that are not really defined by any universal principle, but the individual - thats why “evil” fanatics, Crimsons and so on, even one of Kel’Thuzad’s Horseman are capable to utilize it and no divine punshiment comes down to strip of their power.
What is the ultimate form of domintion and punsihment in the case of the Demons if not Demonology and the art of the Warlocks?
“By divinie right I command thu , vile creature to fight and die in the name of the Light and for me! Again… again… and again! Even Death will not save you from the wrath and the judgment of the Lightforged! By my sanctified blood I will seal our deal, our pact will be your chain and you will kill your own despicable kind because the Light… and ME wills it! OBEY!”
See above
Similar but painfull and different situation
Just becasue you died, you not suddenly forgot how to be a Paladin, wear plate use big swords or hammer or follow the Teachings
Even the Light can and probably will answer you if you are devoted enough
Why?
Gilneans have long tradition in the form of “Harvest Witches”, or the Kul Tirans (who were Gilenan settlers) with the Thornspeakers
Cenarius wasn’t that picky to begin withto teach druidism to anyone he crossed be it mutated Trolls or Tauren ancestors
It is basically nature magic, nothing fancy
(The Celtic peoples say hi, by the way)