The following event took place around 5-6 years ago.

I do not have any great knowledge on this subject, but I have had one experience that I will never forget.

I had a very good friend that I had known for 40 years. He was 80 years old and was in a hospital with an appendicitis.  Thats all I knew at that time.

What happened was that I had to get up at 3 AM to take a medication and decided to go sit in my easy chair and have a smoke. As I was sitting there not thinking about anything in particular a voice in my head spoke and said I died of a heart attack it was just like hearing it over a telephone. I immediately thought of my friend and was enraged at that terrible thought and did all I could to kick it out of my mind. I was not going to give such a terrible thought a home. Usually I can cancel out bad thoughts, but this one would not cancel.

Later in the day, a mutual friend called me and asked if I had heard about John. I said no, what? He then told me that John had died at 2:58 AM that morning.

My friend John had announced his own death to me about 7 minutes after it happened. But that was not the end of it! John spoke to me one more time 30 days later. What he said then was Im going to leave you now. Apparently he had been hanging around me for the last 30 days.

I have never had such an experience before or since. I dont hear voices in my head. But I heard Johns voice, and, if I ever doubted the afterlife, I will never doubt it again.

I need to say that John and I had never discussed contact with the dead before and there was no agreement between us about either of us trying to contact each other when the one of us died. But, both John and I had strong metaphysical beliefs.
My friend John called himself an Edgar Cayce Christian.