February 20

In prayer there is a mingling of station, [with those who have passed on to the next world] a mingling of condition. Pray for them as they pray for you! When you do not know it, and are in a receptive attitude, they are able to make suggestions to you, if you are in difficulty. This sometimes happens in sleep. but there is no phenomenal intercourse! That which seems like phenomenal intercourse has another explanation.” The questioner exclaimed; “But I have heard a voice!” ‘Abdu’l-Bahá said: “Yes, that is possible; we hear voices clearly in dreams. It is not with the physical ear that you heard; the spirit of those that have passed on are freed from sense-life, and do not use physical means. It is not possible to put these great matters into human words; the language of man is the language of children, and man’s explanation often leads astray. 
‘Abdu’l-Baha  (Notes of conversations; ‘Abdu’l-Baha in London’)