Relativity dictates that the sub-light speed and the light speed need to cast that spell for a very long time. An eternity for actual light speed.
Actually everyone moves with the speed of light. But the slower you move through space, the faster you move through time, and vice versa.
So if he moves through space at the speed of light, his clock basically stops.
And ultra-light is worse. He would arrive before he leaves and be younger, too.