Hell teaching brings sickness to the mind, body and soul.
Thinking of history, we can see the sickness which crept into Christendom after the ET doctrine became orthodox.
I think of the Black Death.
I think of the Dark Ages.
I think of unlettered ignorance, and economic stagnation.
I think of the Inquisition.
I think of all those crusades against Muslims and other heretics.
In particular, I think of an incident when crusaders were exterminating an entire town in southern France (in those the area was not even called "France," as that only applied to the area around Paris) during the Albigensian Crusades. A lieutenant reported to his commander that they could scarcely tell the heretics from the faithful. The commander replied, "Kill them all - God will know His own!"
In my own time it has been Godless Communists, and now, "ragheads," and so a large slice of humanity is relegated to terrorist status, and deemed fit only for Hell. If I'm ranting too much, please excuse...