"What is your life ? It is even a vapor, that appeareth for a little time, and then vanisheth away."
     James 4:14

According to Einstein's Theory of relativity, time moves slower for that which moves at the speed of light. This has been proven in an experiment, at least to a clock in jetplane that ticked 'slower' than its stationary counterpart. This means that a person travelling at close to the speed of light would "age" slower than the one staying stationary.
Remember the twin brothers in Einstein's Thought Experiments ? One stays behind while the other leaves for another galaxy at light-speed. For a pun, let us call the spacefaring brother as the "lightspeed twin " who goes by a fast-paced life - whose attitude leans more on the worldy pursuit of temporal things, such as money and toys. His earthbound brother we'll call as the "lifespeed twin" who opts to spend his time on that which is most important - such as relationships and godliness. When the lightspeed brother returns from his voyage after spending a few years on his 'Photonic Ship', he sees his lifespeed brother now old and frail and on his deathbed. Pardon this macabre scenario, but time moves relatively "slower" for that which move at or travel close to the speed of light. Hence the lightspeed brother has aged much slower than his brother that stayed on earth.
Someone who wants to stay young may think that moving fast all the time can slow down the aging process. No one can truly prolong life or delay aging this way because no one can travel at the speed of light. This is the limit that the law of the universe imposes upon anything that has mass : as an object goes faster, it gains more mass - becoming heavier each time its speed increases, therefore requiring more energy if it were to continue moving any faster. Hence, even if you rode on a ship that travelled close to the speed of light, the speed of your thought would be the same as any other human. It will just be the world outside your ship that would seem to whiz by fast-forward. But you yourself, relative to nothing, has a fixed lifetime.
What a poignant analogy from physics to show us that in life, speeding is not always the way to go. Too much speed in fact, slows us down. The time it took for us to wait for the officer to write that speeding ticket cost us more when we broke the speed limit. And the stress to keep up with a fast-paced life is potent enough to warp our faces and add in a year's worth of extra wrinkles. It is worse if one is heading in the wrong direction, one gets doomed quicker.
Of what value then is our Gedankenexperiments here at all ? And what is the speed of life ?
It is amazing that the answer has been uttered 2000 years ago by a person named Jesus. He says, "Ye are the light of the world." (Mt. 5:14) In order to attain the "speed of life", one has to be the light. Being transformed as His light, one will then be cruising at the speed of life in an almost effortless manner, and shining light among men is an easy yoke.

" For with you is the fountain of life; in your light we see light. "
       Psalm 36:9

As to our twins, the lightspeed brother can't help but notice the smile of contentment and joy on his brother's face as he lay dying of old age.
And as he breathed his last, every single one of his family and friends who loves him were there to pay homage to a man who has touched so many lives. He lived a full life each step of the way. With joy, he wholeheartedly offered his life to the absolute Creator who gave him a good 77 years to live out his purpose, one day at a time.
A contented and a joyful life in this world is what God offers to those who choose to accept the Life he offers as a free gift. Real meaning and purpose is found as God transforms one's character into a godly light. And all this is a preparation for the eternal life ahead.

The lightspeed brother still has a full life ahead of him. Thanks to his twin who, shortly before dying, shared the "Good News" to him.
Three days later, he receives a call for a trip to another galaxy. This time he will travel at the speed of life.
Full speed ahead, brother. Godspeed !