Ādi) Śaṅkarācārya works in Sanskrit discuss the unity of the ātman and Nirguna Brahman “brahman without attributes”.He wrote copious commentaries on the Vedic canon (Brahma Sutras, Principal Upanishads and Bhagavad Gita) in support of his thesis.His works elaborate on ideas found in the Upanishads. Shankara’s publications criticised the ritually-oriented Mīmāṃsā school of Hinduism. He also explained the key difference between Hinduism and Buddhism, 
stating that Hinduism asserts “Atman (Soul, Self) exists”, while Buddhism asserts that there is “no Soul, no Self”.
Ādi) Śaṅkarācārya travelled across the Indian subcontinent to propagate his philosophy through discourses and debates with other thinkers. He established the importance of monastic life as sanctioned in the Upanishads and Brahma Sutra, in a time when the Mīmāṃsā school established strict ritualism and ridiculed monasticism. He is reputed to have founded four mathas (“monasteries”), which helped in the historical development, revival and spread of Advaita Vedanta of which he is known as the greatest revivalist. Adi Shankara is believed to be the organiser of the Dashanami monastic order and unified the Shanmata tradition of worship. He is also known as Adi Shankaracharya, Shankara Bhagavatpada, sometimes spelled as Sankaracharya, (Ādi) Śaṅkarācārya, Śaṅkara Bhagavatpāda and Śaṅkara Bhagavatpādācārya.
Just as a stone, a tree, a straw, grain, a mat, a cloth, a pot, and so on, when burned, are reduced to earth (from which they came), so the body and its sense organs, on being burned in the fire of Knowledge, become Knowledge and are absorbed in Brahman, like darkness in the light of the sun.
There is sorrow in finitude. The Self is beyond time, space and objects. It is infinite and hence of the nature of absolute happiness.
Loud speech, profusion of words, and possessing skillfulness in expounding scriptures are merely for the enjoyment of the learned. They do not lead to liberation.
Each thing tends to move towards its own nature. I always desire happiness which is my true nature. My nature is never a burden to me. Happiness is never a burden to me, whilst sorrow is.
Give up identification with this mass of flesh as well as with what thinks it a mass. Both are intellectual imaginations. Recognise your true self as undifferentiated awareness, unaffected by time, past, present or future, and enter Peace.
