It has been said that Sankara was a divine incarnation of the Lord Siva and also the Lord Surya. Sivarahasya says: Thus, Lord Siva, the blue-necked one, will out of his boundless grace, undertake a number of Avatars to establish the orthodox traditions, to help the people in the world. This describes Sankara's life quite well because he established an orthodox Hindu tradition, Advaita, that has helped many around the world.
The Saura Purana, which is an important work, which gives many details about the life of Sankara also has the following: The Lord Surya himself will take on the form of an Avatar as Sankara writing suitable commentaries on the Vyasa Sutras to spread the meaning of the Vedas. This is also something that Sankara did in his short thirty-two years here on earth. The question is this a prophecy or was it written after Sankara lived?
There is no argument that there is plenty of documentation of Sankara's alleged Avatar status, but does this really prove his authenticity? Sankara himself admitted that the highest lord may when he pleases, assume a bodily shape formed of maya, in order thereby to gratify his worshippers. But it seems that he didn't see himself as an Avatar.
There are twelve characteristics of Avatars according to the Hindu tradition. Each one will be compared to Sankara's life to better understand and formulate a reason for the wide spread belief that he was a divine incarnation. The first is, in Hindu belief the Avatar is real. That is, it is a visible and fleshy descent of the divine to the animal or human plane. It would be very difficult to find a historian that would deny that Sankara was alive an present on this earth in human form. There is much debate about the time that he walked the earth, but this is not because he was non-existent. It is because Indian history has no accurate dating system. This is because Indian philosophers and theologians were not worried about recording dates of their works because the works were meant to be timeless.
The second characteristic is that human Avatars take a worldly birth. This happens in various ways, but through human parents. Much of the time the power of the particular god rested in the parents of the Avatar. Sankara's parents names were Sivaguru, his father, and Aryamba, his mother. His father's name includes the name of the God Siva and Sivaguru was also wealthy learned brahmin. Aryamba also gave birth to Sankara when the moon was in the Arda Nakshatra, which has the Lord Siva for it's Adhidevata.
Next, the lives of the Avatars mingle divine and human. Sankara is said to have created a miracle at the young age of eight.
One day, Sri Sankara, in the course of his daily rounds for bhiksha, reached the house of a very poor Brahmin. The Brahmin was so very poor that he himself lived upon the charity of his neighbors. When Sankara reached his house, he was absent on other work. Only his wife was present. She was struck by the magnetic personality of young Sankara and thought that he must be an exhalted divine being, who was capable of showering heavenly grace upon her, and therefore wanted to please him by providing good food to him. But unfortunately, there was not any kind of food available in the house. After elaborate search, she was able to find only a small amalaka fruit. She felt very much distressed and ashamed that she had nothing else except that to give to such a person as Sankara. But out of the fullness of her affection she could not resist herself and came and offered this fruit with all reverence and love to Sankara. As soon as he...