Sanatana
The Kumaras are four sages (rishis) who roam the universe as children from the Puranic texts of Hinduism, generally named Sanaka, Sanatana, Sanandana and Sanatkumara. They are described as the first mind-born creations and sons of the creator-god Brahma. Brahma, who had received the knowledge of the Puranas from the Universal Being (god Himself) Narayana, imbibed this to his Four Kumaras (Sanat Kumaras). Sanat Kumaras then taught the Puranas to Narada. Narada transmitted it to Krishna Dwaipayana who in turn scripted them in monumental epic documents of 18 Puranas. The Vishnu Purana is recorded in two parts, the Vishnu Purana and Naradiya Purana. The teachings of Sankaka of the Kumara brothers are contained in the Naradiya Purana which is also divivided in two parts, the first part containing the teachings of Sanaka and others.
Born from Brahma's mind, the four Kumaras undertook lifelong vows of celibacy (brahmacharya) against the wishes of their father. They are said to wander throughout the materialistic and spiritualistic universe without any desire but with purpose to teach. All four brothers are studied Vedas from their childhood, and always travelled together.
The Bhagavata Purana lists the Kumaras among the twelve Mahajanas (great devotees or bhaktas) who although being eternally liberated souls from birth, still became attracted to the devotional service of Vishnu from their already enlightened state. It also mentions them as being an avatar of Vishnu. They play a significant role in a number of Hindu spiritual traditions, especially those associated with the worship of Vishnu and his avatar Krishna, sometimes even in traditions related to the god Shiva.
Read more about Sanatana: Names, Birth and Mission, Discourses, Visit To Vaikuntha, In Shiva Traditions, Other Legends, In Nimbarka Sampardaya, See Also