I found this in the book “Communicating with Your Guardian Angel”…:
During sleep, the human “Astral” body (the “body” of Desire, Emotion, and Sensibility) is located in the Astral “world.” It is there that it could – that it CAN – converse, if it wished – if it wishes – with those Superior Beings who were its Masters, the Guardian Angels.
In Biblical Hebrew, the same word (phiaynutah) is used to say: Interpretation of dreams, Discovery of deep secrets, and/or Understanding of the language of Guardian Angels.
It is in dreams that Guardian Angels speak to Humans.
I just found out about it now…