According to Kabbalistic sources, sleep is one-sixtieth of death: your soul partially withdraws, awareness recedes, and the inner light steps back. King David slept only 60 breaths without losing his soul because he practiced staying rather than leaving. Sleep is a rehearsal for the soul, not rest.
Chapters
The Zohar says something most people were never meant to hear. Sleep is 1/60th of death. Not as poetry, as mechanism. Baal HaSulam explains, when a person sleeps, the soul withdraws. Not completely, but enough. Awareness leaves, judgment loosens, and the body remains. The inner light steps back. This is why dreams exist, and this is why healing happens, and this is why danger exists. Then the Zohar reveals something strange. King David slept like a horse. 60 breaths, light sleep, no disappearance. But why? Because every deep sleep trains the soul how to leave. Most people practice leaving every night. David practiced staying. The secret is not how long you sleep. The secret is how much of you remains. Sleep is not rest. Sleep is rehearsal. If this disturbed you, good. Save it. Some knowledge is not meant to comfort.