what service did he provide to lord vishnu?
As gatekeeper at Vaikuntha.
Ravana
In the Bhagavata Purana, Ravana and his brother, Kumbhakarna, were said to be reincarnations of Jaya and Vijaya, gatekeepers at Vaikuntha, the abode of Vishnu and were cursed to be born in Earth for their insolence.
what is the relation between kuber and ravan in mythology Kubera is described as the uncle of Ravana in the "Mahabharata". what is this former one worshipped for? He is worshipped as the god of wealth. what significance it has in other religion? In Jainism, he is the attendant Yaksha of the 19th Tirthankar Mallinath. is he a good deity according to the puranas? Yes, as The "Purana"s grant him unquestioned godhood. who is the above mentioned latter god? A king of Lanka and the chief antagonist in the Hindu epic "Ramayana" and its adaptations. where was he born? There are several beliefs, but the people of Bisrakh village in Uttar Pradesh claim that Bisrakh was named after Vishrava, and that Ravana was born there. is he a follower of lord shiva? Yes how is he related to linguistics? He is the composer of the "Ravanabhet" and "Ravaniya". and any medical connection? He is also the composer of the 16th century C.E. scriptures "Nadi Pariksa" and "Nadi Vijnana" on knowledge about the veins.
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Ravana [SEP] As Vishnu's cursed doorkeeper
In the Bhagavata Purana, Ravana and his brother, Kumbhakarna, were said to be reincarnations of Jaya and Vijaya, gatekeepers at Vaikuntha, the abode of Vishnu and were cursed to be born in Earth for their insolence. These gatekeepers refused entry to the Sanatha Kumara monks—- who, because of their powers and austerity, appeared as young children. For their insolence, the monks cursed them to be expelled from Vaikuntha and to be born on Earth. Vishnu agreed that they should be punished. They were given two choices, that they could be born seven times as normal mortals and devotees of Vishnu, or three times as powerful and strong people, but as enemies of Vishnu.