Elixir Field misnamed.

[Brannigan]

Think of it this way:
It's called Hallowed Ground because the PLD is "holding on their ground", and rendering themselves impervious to attacks.
With Deliverance, the WAR is abandoning all their sanity, liberating all their wrath and becoming uncontrollable.

Alternatively,

the skill is called "Invincible" because it makes the paladin invincible. The stance is called Destroyer because it makes you good at destroying things.

In the case of Hallowed Ground, there might be one reason the loc team chose this name (other than Hallowed = sacred = paladin things). A loooooooong time ago in 1.x, shortly after jobs were announced, early drafts of the job ability descriptions were added to the dats. Many of them were the same as they ended up, but for example Warrior's 15 min ability was an AOE stun that woke up sleeping allies (lol) and buffed HP iirc.

PLD's was Invincible/Hallowed Ground, but with one extra thing - it required you to stand still and faded upon movement. Maybe someone on the loc team was like "oh well you can't move so it's like you're consecrating this area" and so we got Hallowed Ground. We also had Holy Succor at the time (now called Clemency), so maybe they were trying to holy up our names.