I myself had the peculiar experience of my father appearing in my room the night he died. He started with an apology, we argued and conversed, and at the end he gave this terrifyng scream and disappeared. Four days later one of my uncles turned up to tell me he’d died four days before. I still remember turning towards the bedroom and thinking, “What the hell was that the other night??”.
But then I dismissed it. I was an atheist at the time, and my next thought was, “Nah! I don’t believe in things like that. It must have been a bad dream or something.”
And that was despite the fact that during the episode I actually asked the question, "What is this? A dream or something?’ My father even looked a bit bemused, and replied “No, it’s not a dream. I died tonight.”
As Christ said, “A man is as he thinks”. I’ll tell you now that atheists, and hardline anti-Catholic Protestants, will dismiss the evidence of incorrupt bodies of saints, for the simple reason that they “don’t believe in those things.”