In dreamless sleep the ego completely disappears, because when there is no thinking, no dreaming, how can you carry a fiction? But dreamless sleep is very small. In eight hours of healthy sleep it is not more than two hours. But only those two hours are revitalizing. If you have two hours of deep dreamless sleep, in the morning you are new, fresh, alive. Life again has a thrill to it, the day seems to be a gift. Everything seems to be new, because you are new. And everything seems to be beautiful, because you are in a beautiful space.
What happened in these two hours when you fell into deep sleep -- what Patanjali calls sushupti, dreamless sleep? The ego disappeared. And the disappearance of the ego has revitalized you, rejuvenated you. With the disappearance of the ego, even though in deep unconsciousness, you had a taste of God.