In Hindu (post-Vedic) tradition, Shesha (IAST: Śeṣa, Devanagari: शेष), also known as Sheshanaga (IAST: Śeṣanāga, Devanagari: शेषनाग) or Adishesha (IAST: Ādi Śeṣa, Devanāgarī: आदिशेष) is the king of all Nagas (serpent deities), one of the primal beings of creation, and according to the Bhagavata Purana, an avatar of the Supreme God known as Narayana. He is also known as Balarama and Sankarshana. In the Puranas, Sheshanaga is said to hold all the planets of the Universe on his hoods and to constantly sing the glories of Vishnu from all his mouths. He is sometimes referred to as Ananta Shesha which translates as endless-Shesha or as Adishesha which means the first Shesha. It is said that when Adishesa uncoils, time moves forward and creation takes place. When he coils back, the universe ceases to exist. "Shesha" in sanskrit texts, especially those relating to mathematical calculation, also implies the "remainder" – that which remains when all else ceases to exist.
Sheshanaga is also considered a dasa (servant) as well as also a manifestation, or avatar, of Lord Maha Vishnu himself. Ananta Sheshanaga is said to have descended to Earth in four human forms or avatars: Lakshmana, brother of Lord Sri Rama, Balarama, brother of Lord Sri Krishna, Ramanuja and Manavala Mamunigal. Maharsi Patanjali the major compiler of yogic traditions is also considered to be an incarnation of the great Shesha.
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