Agastya is one of the Saptarshis who are extolled at many places in the Vedas and a revered Vedic sage and earliest Siddhar. He is also believed to be the author of Agastya Samhita. Agastya the Muni, son of Urvashi was born of both Gods, Mitra and Varuna. Siddhar were spiritual adepts who possessed the ashta siddhis, or the eight supernatural powers. Sage Agathiyar is considered the guru of all Siddhars, and the Siddha medicine system is believed to have been handed over to him by Lord Muruga, son of the Hindu God Lord Shiva and Goddess Parvathi. Siddhars are the followers of Lord Shiva. Agathiyar is the first Siddhar. His disciples and other siddhars contributed thousands of texts on Siddhar literature, including medicine and form the propounders of the system in this world. He is considered as the Father of Tamil literature and compiled the first Tamil grammar called Agathiyam. He is regarded to have lived in the 6th or 7th century B.C and specialized in language, alchemy, medicine and spirituality (yogam and gnanam).