Sri Agastyar Rishi or Siddha Agastyar is the first Siddha of the lineage of 19 Siddhas. Agastyar is a Maha-Rishi (great seer) and is also one of the Sapta Rishis (seven seers). He is considered a father of traditional Indian Ayurvedic medicine and is said to have been the author of several writings in this field. He is also the one who transmitted the well-known Kalari massage.

Agastya was also an astrologer, alchemist and yogi. In the Ramayana, an ancient Indian scripture, his work is written about several times. Agastya is considered one of the main initiators and writers of the palm leaf libraries in India and Bali.

Agastya was also the one who brought Vedic knowledge from India to Java to Indonesia, from where it spread to Bali. On Java, there are several temples dedicated to him and Shiva. 

Agastya had a wife, Lubamitra, with whom he is said to have been very happy. They had a son together, named Dridhasyu, who became a rishi himself. Today, they both work from the subtle worlds and through the Jiva Nadi (palm leaf library).