Don't take it so personally
You're not the only one
That time has got it in for, honey
That's where you're wrong
Arctic Monkeys lyrics aside, what I mean to say is:
No religions are ever mentioned in FFIV, but the game has religious allegory surrounding literally everything within its setting, and the Paladin is referred to even in the original Japanese as a, "Sacred" or "Holy" knight, and those words are strictly tied to religion.
Keep in mind that the White Mage Rosa, and by association, the other White Mages within FFIV have the, "Pray" command as an action command (removed due to censorship of religious themes in English).
When used, if the Prayer succeeds, it recovers HP. Later, uncensored remakes have it restore MP as well. When it fails, you get a line, "The Prayer did not reach Heaven."
In Mysidia, Cecil walks into, "The House of Prayers" which was censored to, "House of Wishes." He is put on the path to becoming a Paladin by the elder sage that presides over that house and Mysidia.
Cecil's PLD uses White Magic exclusively.
More than that, The Mountain of the Ordeal has mountain stations in the original text. Mountain stations are commonly used on trail maps on mountains to denote location. But of importance here is that the stations you come across are direct references to the Stations of The Cross from Catholicism. They reference the 3rd and 7th, which are the first two times that Jesus falls while carrying the cross.
Then there's the Four Fiends being, "The Four Heavenly Kings" in JP, which is a common Buddhism reference or whatever, but the choice of their names references Dante's Inferno, which is a story that imagines what Christian Hell is like.
I'm sure there's other references throughout, but I can only recall so much on demand. The last one I can recall being the Mysidian Elder imploring all of the side characters to pray for Cecil and the party when they face off against Zeromus, which is the soul of Zemus. Zemus is the Amharic word for Prayer, making Zeromus a play on words equating to, "No Prayer."
So, while no in game god or religion is ever mentioned, the real world religion of Christianity is tied in explicitly, and there's religious framing around the main antagonist.
Keep in mind, too, that Cecil's character is all about repentance for his past evil ways and finding that not just justice, but mercy and forgiveness(for others and himself), are ways of righteousness, too. Something commonly espoused by Christianity.
Phew. That aside, I am happy that you see HW PLD quests as bad, because they really really are.