Energy is perpetually in motion.
Matter is subject to the entropy, friction & resistance of other matter.
Space is naturally free of all entropy, friction or resistance.
Matter moves in space in perpetual motion.
Electrons spin in perpetual motion around an atomic nucleus.
Planets orbit in perpetual motion around their parent star.
Stars rotate in perpetual motion around their galactic centre.
Space is the medium that allows perpetual motion to be experienced.
Time is the distance through space that energy is in perpetual motion.
The perpetual nature of time is called eternity.
The perpetual nature of space is called infinity.
The perpetual motion of reality is called nature.
It is the nature of the universe to be infinite, eternal & perpetual.