The Shechinah (שכינה), God's indwelling Presence, rests in the Holy of Holies. But if God fills the entire world with His glory, what does it mean for the Shechinah to "rest" in one specific place?
Rabbi Schneur Zalman of Liadi answers with an analogy from the human soul. Your soul pervades all 248 organs of your body, from your head to your feet. Yet its principal dwelling place is in the brain. From there, it sends different powers to different organs: the eye receives the power to see, the ear to hear, the mouth to speak, the feet to walk. You can feel this directly, sitting in your brain, conscious of everything that happens throughout the body.
But here is the crucial point: these differences in how the organs receive their power have nothing to do with the soul's essence. The soul is not "more present" in the brain than in the feet. It is a single, simple, spiritual entity with no physical shape or spatial dimension. It cannot be divided into 248 pieces.
Rather, the soul contains 613 distinct powers, corresponding to the 248 positive and 365 negative commandments, and these powers flow outward from concealment through the brain as their primary channel. The brain is not where the soul "is." It is where the soul's life-force first becomes manifest before flowing to the rest of the body.
God's relationship to the universe works the same way. God is equally present everywhere. But the Shechinah, the revealed flow of divine vitality to all worlds, has its primary point of manifestation. In the time of the Temple, that point was the Holy of Holies. The Ark, the Tablets, the Ten Commandments engraved on stone by God's own hand, these were not merely housed there. They were the channel through which infinite light entered finite reality.