This has been preying on my mind for a while…
Ask a christian what they believe will happen to you when you die if you don’t believe in or worship their god. When they finally state that you will go to hell, ask them if they think that you should be tortured for eternity for simply not believing what they believe.
Finish off by mentioning that after only having known them for a few minutes, they seem quite OK with the notion that you will suffer in agony forever, regardless of the good you have done during your entire life.
Ask them how they can ever expect you to be their friend or trust them.
When I first read that, atheist though I am, I found it quite shocking. Mainly because I hadn’t thought about its inevitable conclusion much before.
But now that I think about it, I realise that I am always wary of people who profess to be christians. Maybe subconsciously this is the reason.