"The Divine problem is to call.
The human problem is to know who is calling.
You find it throughout the Bible and later, the constant question:
Whose voice is it?
Some people think that the mere fact of having a supernatural parapsychological experience is meaningful.
But such an experience is just that: a parapsychological experience, and that’s the end of it.
Merely hearing voices does not mean that one has heard the voice of God, and that is always the big temptation and the downfall of quite a number of people.
There are some who are cheats, meaning people who never had an experience, and are just imitating.
But there are many people who really heard something, and their very big mistake was that they didn’t identify the voice.
There is another biblical quotation:
When Gideon has his experience, he hears a voice and he says, “God, how shall I know that you are speaking to me?”
This is in many ways the most pertinent question.
“Give me a sign that it is You who are speaking to me” (Judges 6:17)."
From an interview in Parabola called "The Command to Hear"