God was One – when He wished to be many, there was vibration, and this vibration resulted in two aspects: Light and Sound.
These two principles proceed from the Absolute Lord and are the way back to Him, the path that Masters have taught through practical and scientific experience. You will find symbols of Light and Sound in most of the religious places, and they represent the true Light and Sound of God which already exist within the man-body.
The inner Sound principle is All-Conscious and too subtle for the ears, the tongue, and the pen. It is an unwritten law and an unspoken language. It is self-existing, self-sustaining and self-supporting and yet is the very life of all that exists both in the animate and inanimate creation. But it can be realized in the deepest depth of the soul, for the two are the same essence, the soul being but a drop of the Ocean of All-consciousness.
Sant Kirpal Singh