Adi Sankara was the first philosopher to consolidate the doctrine of Advaita Vedanta. His teachings are based on the Upanishadic ideal of unity of the individual Self and Brahman. Sankara is regarded as an incarnation of Lord Siva.
Sankara toured India with the purpose of propagating the Upanishadic tenets through discourses and debates with other philosophers. He founded four mathas (monasteries) which played a key role in the historical development, revival, and spread of post-Buddhist Hinduism and Advaita Vedanta.
Sankara's parents were Sivaguru and Aryamba. They were childless for many years. They prayed at the Vadakkumnathan temple in Trichur, Kerala, for a child. Legend has it that Lord Siva appeared to both husband and wife in their dreams, after which a son was born to them. He was named Sankara (bestower of goodness), in honour of Lord Siva (one of whose epithets is Sankara).
As a child, Sankara showed remarkable scholarship, mastering the four Vedas by the age of eight. Following the customs of those days, Sankara studied and lived at the home of his teacher.
Once, while accepting bhiksa (food received as sacred alms from a householder), Sankara came upon a woman who had only a single dried Amalaka (gooseberry) fruit to eat which she willingly offered to Sankara as bhiksa. Moved by her nobility, Sankara composed the Kanakadhara-stotra on the spot. Legend has it that on completion of this hymn, golden amalaka fruits started showering in her home by the grace of Lakshmi, the Goddess of wealth.
From a young age, Sankara was attracted to sannyasa (monastic life). His mother was against his becoming a monk, and refused him formal permission. Story goes that once during a bath in the river, Sankara was caught by a crocodile. In the face of near death, Sankara asked to be allowed to take sannyasa (Apat-sannyasa), and mother Aryamba reluctantly agreed. Sankara immediately recited the mantras to make a renunciate of himself. Miraculously, the crocodile released him and Sankara emerged unscathed from the water.
Sankara left Kerala and travelled towards North India in search of his Guru. On the banks of the river Narmada, he met Govinda Bhagavatpada, the disciple of Gaudapadacharya. When Govinda Bhagavatpada asked Sankara for his identity, he replied with extempore verses, called Dashashloki, that succinctly brought out the entire Advaita philosophy. Govinda Bhagavatpada was impressed, took Sankara as his disciple, and taught him the Advaita Vedanta teachings enshrined in the Upanishads. Sankara was later commissioned by his Guru to write a commentary on the Brahma-sutras and propagate Advaita Vedanta.
The Madhaviya-sankaravijaya states that Sankara once calmed a flood from the river Reva, thus saving his Guru, who was absorbed in samadhi (absorption) in a cave nearby.
On his mission to spread Advaita Vedanta, Sankara travelled to Kashi, where a young man named Sanandana from Choladesha (present day Trichy-Thanjavur in Tamil Nadu, South India) became his first disciple. In Kashi, Sankara was on his way to the Vishvanatha Temple, when he came upon a chandala (untouchable) with four dogs. When asked to move aside by Sankara's disciples, the untouchable replied, "Do you wish that I move my everlasting Atman (the Self), or this body made of food?" Understanding that the untouchable was none other than Lord Shiva, and his dogs the four Vedas, Sankara prostrated himself before him, composing extempore, five verses known as Manisha Panchakam.
On reaching Badari in the Himalayas, he wrote the famous bhashyas (commentaries) on the prasthana-traya (Upanishads, Bhagavad Gita, and Brahmasutra) and prakarana-granthas (introductory texts on Vedanta). He later taught these commentaries to his disciples. Some, like Sanandana, were quick to grasp the essence; Sankara once summoned Sanandana from one bank of the river Ganga, while he was on the opposite bank. Sanandana crossed the river by walking on the lotuses that emerged wherever he placed his foot. Sankara blessed him with the name ‘Padmapada’ (lotus-footed one).
One of the most famous debates of Sankara was with the ritualist Mandana Mishra. Mandana Mishra's Guru was the famous Mimamsa philosopher, Kumarila Bhatta. Sankara sought a debate with Kumarila Bhatta but he directed Sankara to meet his student Mandana Mishra and debate with him instead.
During this debate, the wife of Mandana Mishra, the learned and wise Ubhaya-bharati, was the referee. After debating for over 15 days, Mandana Mishra accepted defeat. Legend has it that Ubhaya-bharati then challenged Sankara to have a debate with her in order to 'complete' the victory. This debate was to be on the subject of kama-sastra (science of love). But Sankara, being a renunciate from his childhood, had no knowledge of this subject; thus, after requesting for some time before entering into this fresh debate, he entered the body of a dead king by his yogic powers and acquired the knowledge of kama-sastra. Later, however, Ubhaya-bharati declined to debate with him and allowed her husband Mandana Mishra to accept sannyasa with the monastic name 'Sureshvaracharya’ as per the agreed rules of the debate.
Sankara then travelled with his disciples to Maharashtra and Srisailam. In Srisailam, he composed Sivananda Lahari, a devotional hymn to Lord Shiva. On another occasion, when Sankara was about to be sacrificed by a Kapalika, Lord Narasimha appeared, on Padmapada's prayer to save Sankara. Sankara then composed the Lakshmi Narasimha-stotra.
He then travelled to Gokarna, the temple of Hari-Sankara and the Mookambika temple at Kollur. At Kollur, he accepted as his disciple a boy believed to be dumb by his parents. He gave him the name, Hastaamalaka. Next, he visited Sringeri to establish the Sarada-pitham. It was here that Totakacharya met him and went on to become another of his important disciples.
After this, Sankara began a Dig-vijaya (missionary tour) for the propagation of the Advaita philosophy by winning over all philosophies opposed to it. He travelled throughout India, from the South to Kashmir and Nepal, preaching to the local populace and debating philosophy with Hindu, Buddhist, and other scholars and monks along the way. With the Kerala King Sudhanva as companion, Sankara passed through Tamil Nadu, Andhra Pradesh and Vidarbha. He passed through Karnataka and reached Gokarna where Sankara defeated in debate the noted Saiva scholar, Nilakantha. Proceeding to Gujarat he humbled Bhatta Bhaskara, the proponent of Bhedabheda philosophy in Dvaraka.
The Jains were also defeated in philosophical debates at a place called Bahlika. Thereafter, the Acharya established his victory over several philosophers and ascetics in the region of North Kashmir, Darada (Dabistan) . Later, he had an encounter with a Tantrika, Navagupta, at Kamarupa (present day Assam), and he too accepted the supremacy of Sankara's vedantic teachings.
Sankara visited Sarada-pitham (that houses the Sarvajna-pitham or Throne of Omniscience) in Kashmir (now in Pakistan-occupied Kashmir). This temple had four doors for scholars from the four cardinal directions. The southern door (representing South India) had never been opened, indicating that no scholar from South India had ascended the Sarvajna-pitham. Sankara opened the southern door by defeating in debate all the scholars there in all the various scholastic disciplines, such as Mimamsa, Nyaya, Vedanta and other branches of Hindu philosophy. He then ascended the Sarvajna-pitham (Throne of Omniscience).
Toward the end of his life, Sankara travelled to the Himalayan area of Kedarnath-Badarinath, and attained Videha-mukti (freedom from embodiment). There is a samadhi-shrine dedicated to Sankara behind the Kedarnath temple. However, there are variant traditions on the location of his last days — some opining that it was Kanchi in Tamilnadu and others saying Trichur in Kerala.
Sankara founded four Mathas to guide the Hindu religion: Sringeri in Karnataka in the south, Dvaraka in Gujarat in the west, Puri in Orissa in the east, and Jyotirmath (Joshimath) in Uttarakhand in the north. Tradition states that he put in charge of these mathas his four main disciples: Suresvaracharya, Hastamalakacharya, Padmapadacharya and Totakacharya respectively. The present heads of the mathas trace their authority back to these figures. Each of the heads of these four mathas takes the title of Sankaracharya (the teacher Sankara) after the first Sankaracharya.
We conclude this section with a well-known verse, recited in praise of Adi Sankara:
"I salute Sankara
compassionate abode of
the Vedas, Smrtis, and
Puranas, who bestows
auspiciousness on the entire world."