By the influence of eternal time, which is a representative of the Supreme Personality of Godhead, the father begets a son, and the father dies by the influence of cruel death. But by times influence, even the lord of cruel death is killed. In other words, all the demigods within the material world are temporary, like ourselves. Our lives last for one hundred years at the most, and similarly, although their lives may last for millions and billions of years, the demigods are not eternal. No one can live within this material world eternally. The phenomenal world is created, maintained and destroyed by the finger signal of the Supreme Personality of Godhead. Therefore a devotee does not desire anything in this material world. A devotee desires only to serve the Supreme Personality of Godhead. This servitude exists eternally; the Lord exists eternally, His servitor exists eternally, and the service exists eternally.