As stated in Bhagavad-gita (7.20), kamais tais tair hrta jnanah prapadyante nya-devatah. Those whose minds are distorted by material desires surrender unto demigods. A demigod cannot become master, for the real master is the Supreme Personality of Godhead. The demigods, to keep their prestigious positions, bestow upon their worshipers whatever benedictions the worshipers want. For example, once it was found that an asura took a benediction from Lord Siva by which the asura would be able to kill someone simply by placing his hands on that persons head. Such benedictions are possible to receive from the demigods. If one worships the Supreme Personality of Godhead, however, the Lord will never offer him such condemned benedictions. On the contrary, it is said in the Srimad-Bhagavatam (10.88.8), yasyaham anugrhnami harisye tad-dhanam sanaih. If one is too materialistic but at the same time wants to be a servant of the Supreme Lord, the Lord, because of His supreme compassion for the devotee, takes away all his material opulences and obliges him to be a pure devotee of the Lord. Prahlada Maharaja distinguishes between the pure devotee and the pure master. The Lord is the pure master, the supreme master, whereas an unalloyed devotee with no material motives is the pure servant. One who has materialistic motivations cannot become a servant, and one who unnecessarily bestows benedictions upon his servant to keep his own prestigious position is not a real master.