But even today Natha cult is alive in small pockets as an independent movement. Therefore, any argument that Buddhists turned Brahmans because of this cult in this region can not be ascertained for surety. But there are couple of things that I find rather intriguing.
There is a rather curious tradition among Malayali Brahmins. The Namboodiris who are temple priests were excluded from Vedic studies. The Vedic beginning of Tantra has always been suspect. In fact, it rather sounds like ghostistic than godistic in its worship of a deity. That is, the priest gets possessed by the deity before the ritual.
Ravi Mundkur gives the following account on origin of Matsyendranatha, a dominant figure of Natha cult(by legends),
Macchendra (Matsyendra) Natha hailed from a fisher community of probably Bengal area. (However, the sculptures show him riding on fish and the legends metaphorically describe his birth from the semen of Shiva swallowed by a fish).
Then we have Grama Paddhati account, a manuscript belonging to Tuluva Brahmins, on the dual origin of Tuluva brahmins(probably, both Tulu and Malayali Brahmins). According to legends;
-> Parashurama upgraded fishermen to Brahminhood
-> Kadamba kings brought Brahmin families from Godavari region and settled them here
If one understands the polluting character of fish and in turn fishermen in caste system then Parashurama account sounds rather strange. Why fishermen?
That, in my opinion, can be explained if those are Matsyendranatha's Brahmins.
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