So that sound is a plant and that light is a plant, and if we let it grow, then we find the true God, sach khand.
There is so much joy and love in Sach Khand. And it never ends. It is eternal and infinite.
And to get this bliss you have to complete 3 courses, one is dhyan - which is undivided attention to the third eye, the other is simran, the remembrance of God in 5 names - and the third is the sound current, listening to the sound current.
When you have completed all these courses, you begin to fly out of this body and wander around in the higher dimensions and come back here. (Sant Khem Singh ji).