Śaivism is a very ancient branch of Hindu religion. Rooted in the Vedas and āgamas, it has been developed into a formidable religio-philosophical system by a galaxy of mystics and writers. An important teacher often quoted especially by the Vīraśaiva writers is Aghora Śivācārya, a pontiff of the Āmardaka monastery at Cidambaram (Tamil Nadu) who probably lived in the 11th-12th cent. A. D. Tattva-prakāśa of king Bhoja of Dhārā is said to be a fundamental work on Śaivism. Aghora Śivācārya is reputed to have written a detailed commentary on this work, refuting the highly monistic interpretations of an earlier commentator Śrīkumāra. Another work usually attribu-ted to him is Mṛgendrāgama-vṛtti-dipikā, a commentary on the famous Śaivāgama, Mṛgendrāgama. He is credited with the authorship of several other works also like Aghora-śivapaddhati, Tattvasaṅgraha, Mahotsavanidhi and so on.