Spiritual knowledge is a regular science. Just as two and two make four, similarly everything is clean and obvious here also and there is no scope for any kind of modification or change in that.
"The Saints and the true devotees of God have all told of the Light and Sound. Whatever references I have found, by parallel study of religions, I have incorporated into the book "Naam or Word"; so if you are interested in the references you will find them there."
Sant Kirpal Singh
First edition 1960