Padma Purana

Vyas said--- One who wears a Rudraksha rosary is supreme among all human beings. The mere sight of such a holy man absolves people of their sin. A Rudraksha bead bears features of a Linga and yoni on it's surface. One should not wear a rudraksha on which above mentioned features are absent. Similarly two joint beads should never be worn. All the mantras become doubly powerful when chanted with the help of rudraksha-rosary.During Satya-yuga, there lived a mighty demon named Tripurasur. He had conquered the deities and was capable of moving in the space. The deities sought help of Lord Shiva, who killed Tripurasur by the sight of his third-eye. In the process, few drops of sweat, emanating from Shiva's body fell down on the earth. These sweat drops got transformed into a large Rudraksha-tree.

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