Studying physics the other day, a strange and wonderful fact came to my attention. According to Einstein's theory of special relativity, the faster an object goes (most noticeably, as it approaches the speed of light) the more, to an outside observer, it slows down in time. If and when that object hits the speed of light, time stops completely — the object can grow no older. We all hurtle through the space-time continuum, but when we divert all possible velocity into movement through space none is left over for temporal change. Our time simply comes to a halt.

In the words of Brian Greene, physicist-author of The Elegant Universe, "Thus light does not get old: a photon that emerged from the big bang is the same age today as it was then. There is no passage of time at light speed." We can observe these photons, now stretched out to the length of microwaves, bathing the entirety of the universe.

Through the ages philosophers and theologians have searched for an eternal in the immaterial realm — the ideal Form, the disembodied God — yet the eternal surrounds us right here. Flip on a light switch and there it is — your room is filled with particles destined for immortality. They will be here billions of years after that light bulb (and your and my body) has burned out. And marvelously, they will not age one whit over these millennia but still cavort like fresh-born babies. Time without end, amen.

Only thus do we sense the full meaning of "And God said, 'Let there be light.' " In light, eternity plunged into time, and yet retained its eternal form. At the heart of change we find the unchanging. At the speed of light — the swiftest of all motions — we find what is ever still. Realize this and become enlightened.

Today, turn on a light switch and witness a miracle. Realize the eternal nature of these dancing photons.

Drew Leder in Sparks of the Divine