איוב, פרק ד׳, פסוק י״ג

The transition between waking and sleeping is a unique window of time. As the mind disconnects from the burdens of the day, it becomes uniquely open to receiving higher messages. The stillness of the night, marked by the descent of deep sleep, provides fertile ground for elevated visions and revelations to take hold [ביאור שטיינזלץ, רמב״ן].

The primary approach among commentators is that the mind during this period is simply filled with thoughts [רש״י, אבן עזרא, מצודת ציון]. Elaborating on this mental state, [מלבי״ם] explains that these thoughts are often disorganized and scattered. Driven by the imagination, they branch out in many directions much like the limbs of a tree. This typically occurs at the beginning of the night. Exhausted from the day's worries, a person falls into a deep sleep, yet their mind remains active with the images and ideas they pondered while awake [מצודת דוד]. At this early stage of rest, the mind is caught in a foggy state. Truth begins to sparkle through a heavy screen of imagination, leaving the essential message mixed with trivial details [מלבי״ם].

Offering a different perspective, [אלשיך] argues that the onset of deep sleep serves to validate the vision rather than confuse it. In this view, the deep sleep completely separates the experience from any residual daily thoughts. Eliphaz, the speaker sharing his experience, wants to assure Job that his vision was not a product of his own waking worries or personal musings about Job's suffering. The fact that this vision occurred during a state of deep sleep proves its authenticity. It happened at a time when all ordinary human thoughts naturally fade away. This demonstrates that the message was a true, external revelation received in complete isolation, rather than a mere invention of his own heart.