Of all the Sastha temples in South India, the Sree Dharma Sastha Temple at Sabarimala is the most famous. The deity of this temple is popularly called Swami Ayyappan.
The word Sastha simply means teacher. It is not exactly clear how the warrior God Ayyappan whom the whole of South India worships as Harihara Suthan (the son of Vishnu and Shiva) became Sastha. According to Brahmanda Purana, a Sanskrit work written prior to 7th century, Ayyappan or Sastha is the son of Lord Vishnu and Lord Shiva.
The annual Sabarimala Pilgrimage attracts millions of pilgrims from all over India to the Dharma Sastha Temple at Sabarimala. The pilgrimage begins mid-November and ends mid-January.
Unlike typical Hindu Gods, who are usually depicted as married with children, Ayyappan or Dharma Sastha is a celibate. There is an interesting twist here. Some Sastha temples in Kerala also worship Ayyappan as a householder with two wives – Purna (perfection) and Pushkala (prosperity). He also has a son called Satyaka (truthfulness). However, Sabarimala Ayyappan has no wife or children and his name is synonymous with celibacy. Celibacy also forms an important part of the austerities pilgrims are required to observe.