I have been thinking about this relationship recently. We always hear that Sankara is Siva. The only form of support I can remember hearing is that he came to reinstill faith in the Veda in the wake of Buddha. Alone this does not seem like a very sturdy stance. Is there more reasoning/ sastra pramana I am unaware of? If so could someone fill me in? It just seems a little too convenient, especially if this is the sole backing.
Srila Krishna das Kaviraja has Mahaprabhu citing a Padma Purana verse in his discussion with Sarvabhauma:
"[Lord Siva informed goddess Durga, the superintendent of the material world:] ‘In the Age of Kali I take the form of a brahmana and explain the Vedas through false scriptures in an atheistic way, similar to Buddhist philosophy.'" (Madhya 6.182)