That One, though motionless, is swifter than the mind. The
senses can never overtake It, for It ever goes before. Though
immovable, It travels faster than those who run. By It the
all-pervading air sustains all living beings.
This verse explains the character of the Atman or Self. A finite
object can be taken from one place and put in another, but it can
only occupy one space at a time. The Atman, however, is present
everywhere; hence, though one may run with the greatest swiftness
to overtake It, already It is there before him.
Even the all-pervading air must be supported by this Self, since
It is infinite; and as nothing can live without breathing air,
all living things must draw their life from the Cosmic Self.
The Upanishads translated by Swami Paramananda
Text from: Project Gutenberg