Like the blue sky, He arches over everything
Dharma-kaya is the substance of the Dharma; that is, it is the substance of Truth itself. In the aspects of Essence, Buddha has no shape or color, and since Buddha has no shape and color, He comes from nowhere and there is nowhere for Him to go. Like the blue sky, He arches over everything, and since He is all things, He lacks nothing.
He does not exist because people think He exists; neither does He disappear because people forget Him. He is under no particular compulsion to appear when people are happy and comfortable, neither is it necessary for Him to disappear when people are inattentive and idle. Buddha transcends every conceivable direction of human thought.
Buddha's body in this aspect fills every corner of the universe; it reaches everywhere, it exists forever, regardless of whether people believe in Him or doubt His existence.
The Form of Buddha and his Virtues
The Teaching of Buddha
Bukkyo Dendo Kyokai (Buddhist Promoting Foundation),
Toppan Printing Co. (S) Pte. Ltd., 1990
page 52