I have talked to many people I knew in their bodily life, and our conversations have continued a long time, over months and through a year. Our voices were as clear to each other as voices are among friends in this world, but they were heard internally. Sometimes we also engaged in discussions about the human condition after death. They were astounded that no one who is alive in the body knows or believes that she or he will live on after physical life ends, when the truth is that life continues, and continues in such a way that it passes from darkness into broad daylight. For those who believe in the Lord, life grows clearer and clearer.
These people wanted me to tell their friends [on earth] that they were alive and to send letters describing their current status. They themselves had heard much from me about how those friends were doing. “But,”I said, “if I were to say or write the things you ask, your friends would not believe me. They would accuse me of hallucinating, laugh at me, and demand signs or miracles before believing. So I would be exposed to their ridicule. Few, perhaps, would believe that those things were true, because they deny at heart that spirits exist. Even those who do not deny are completely unwilling to hear that anyone could talk with spirits.”
Such beliefs about spirits never existed in ancient times, only in modern times, when people desire to investigate what the spirit is in a highly intellectual way that relies on skewed logic. With their definitions and theories they deprive spirits of all sensation, and the more erudite they claim to be, the more they do so.
from Secrets of Heaven, Volume 1, Sections 448