I tell them I'm Satan and I'm fireproof. Then I ask, is your mouth getting dry and your vision blurred?
Works every time.

I laugh because the way Christian religion works even Hitler and Stalin are in Heaven. The get out of hell card is to simply confess your sins to Jesus and believe in him and all your sins are forgiven. Sorry if folks like Hitler and Stalin can be admitted to Heaven thats a club I'm not interested in spending an eternity with.

I simply tell them that any religion that uses threats like hell to get people to pay money to the church, is not a religion, but a terrorist organisation and I do not negotiate with terrorists

I’m not a good example of what to do in that situation

I saw in life same bad or goood things happen to religious people and non religious people. My mother was very religious and I saw her suffer a lot before her death. I may suffer or may not before I die. I believe in things that I experienced but not the imaginary ones. No one saw the hell or the heaven. No one. claim the god to be kind and a punisher does not go together. If there would be a loving god she would not punish anyone.

I've had people tell me that I hope I find my way back to Christ. I give them the side-eye and either continue my day or say, "yeah, I hope I don't become that weak again."

Depends on their own religious beliefs, after all Hell is NOT originally a Christian concept, ONLY came to be called Hell after the Norse religious belief of the Nordic Goddess Hel whose domain was named after her as she had special place for rapists, murderers and kiddy fiddlers, so I have no problem when I am condemned to Hell as it doesn't exist, IF I was to beleive in ANY Middle East beliefs then reading the Bible Hell as they call it is here on Earth, read what it says "And St Michael the Archangel defeated Satan and his hordes and God gave unto Satan as his domain" so if I was Christian Jewish or Islamic they ought to come to the conclusion we are all in Hel already.

The last time a Theist, a guy I've known for 20+ years, tried to get me back to "The Rooms", (A.A. is a theistic organization) I sent him a strongly worded email with a FB post backing it up, telling him point by point what it was like living with a severe, chronic illness was like.
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After the litany of horrors I experience every day, I asked him "do you really think your gawd has anything I would possibly want?".
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He unfriended me on FB and has said NOTHING to me since.
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Friend? At one time I called him my best friend. Now he's just another Theist who has nothing for me.
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He didn't threaten me with hell. That would have been honest. But had I still cared about him, I would have been devestated. In hell.
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But I'd been shunned by family and friends. He was powerless over me.
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I explain how that is manipulative emotional blackmail and aks them to prove that claim.
Only people online do this, probably because they are afraid of getting told out in person.

I almost never encounter this, as I have never been a Christian and do not surround myself with such people. But when it happens, depending on how pugnacious I'm feeling, I will either 1) laugh; or 2) Say, "screw your god, let him strike me dead right now if he exists".

I don't care as heaven and hill don't exist!

Don't care as nothing will happen, heaven and hell are,in my opinion, hoaxes!

I tell them that heaven has always scared me and that I think I'd be happier elsewhere. If that doesn't scare them off then maybe we can have a decent conversation. If they start to yell, though, I just walk away.

Obviously its uncomfortable to hear any threat of religious punishment, real or otherwise. I have found that calmly and politely explaining to them that they can't threaten you with something you don't believe in. Now you have to realize from their perspective that they are attempting to save you from hell/damnation. When they say they are trying to save you, say you can't save someone who doesn't subscribe to the same worldview.

Educating them politely and non-judgmentally may actually slightly open up their worldview and not threaten the next person with religious punishment

I hold a solemn poise. A straight face. Thinking how I once used this against people i thought needed a little nudge in my direction, i thank them for their concern and move away from them. They have a conviction working on their heart. They want to save me from a damnation. I understand them. I don't challenge their belief or make any statements against it. Our belief comes gradually with some people. It scares others. Just avoid the argument and be polite. Your knowledge and advice is not wanted.

Are you my guide?

Laughter

I laugh.

Simple! For me, an atheist, there is no heavan or hell.

It's your hell. You go there.

I am very rude and laugh at them.Very impolite and un-English!

I tell them I'll have lotsa friends there to party with.

I just tell them that if there is such a place, which we have no proof it this places existence, that I would be in great company and enjoy myself immensely. Then,, I tell them of some of the people who were clearly atheists who have already died, e.g., Mark Twain, John Lennon, Hitchens, Carl Sagan, Karl Marx, etc etc.

I laugh, that shit is funny

I tell them that their God is ever merciful... Oh and that they aren't God lol xD