.... there is a rather widespread view that one of the two Kalais represents, people from the lower castes who converted to vaishnavism as also brahmin status whereas the other kalai represents original (smartha) brahmins who converted to vaishnavism and visishtadvaita. I have heard this from one Iyengar source itself.
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......, it looks to me that the reason for such deep-rooted differences between the two "kalais" could not have been simple philosophical disputes but has to be one of caste-based prejudices.
Dear Sangom, yes, lots of Iyengars think Thenkalais are NB converts, especially the Vadakalai kind, but this view is simply untrue. I have studied this issue and written about it for a long time and in various forums, including this one. There is absolutely no textual evidence that supports this view. For every fair-skinned Vadakalai there are as many dark-skinned Vadakalai and there are as many fair-skinned Thenkalai. So, these anecdotal observations have no validity at all as well.
Most NB SVs are indeed Thenkalais, but not all, there are some Vadakalai NBs as well, i.e. using Vadakalai thiruman and associating with Vadakalai acharyas. If NB converts to SV are Thenkalais Brahmins, then why are there still NB Thenkalais? They must all be Brahmin Thenkalai Iyengars, isn't?
There are no conclusive written record that shows when exactly the final break into two kalais took place. But the doctrinal differences can be seen in the texts starting from, some say, even as early as Ramanuja's period itself. Even less of a record exists who converted to SV when. One famous episode of conversion recorded is one in which Parasara Bhattar (second Acharya after Ramanuja) converted a Brahmin from Karnataka into SV, and he latter became the next Acharya called Nanjeeyar. He is a prominent acharya in the Thenkalai lineage as well as Ahobila Matam lineage. So, the one known case of conversion was a Brahmin to Thenkalai.
Right from the very start SV tradition deemphasized jAti and emphasized bhakti and service. There are Azhvar pasurams that boldly declare that any devotee of Sriman Narayana must be treated as one's master even if he belongs to the lowliest of low jAti, and those who think low of the jAti of a devotee are the real lowly creatures, etc., etc. Periya Nambi before Ramanuja performed the last rites to a Dalit schoolmate and for this reason he faced excommunication from his Brahmin cohorts. There are stories about Ramanuja opening up temples for Dalits. He called them
திருக்குலத்தோர் -- sounds like Harijan of Gandhi doesn't, but this was more than 1000 years ago?
But, Ramanuja didn't reject the Varna system outright. On the contrary, he accepted the Dharmashasthre as as the distilled essence of Vedic teachings. All he wanted to do was to be inclusive in SV worship. He still maintained Brahmin exclusivity in temple aradhanai inside the sannidhi which included touching the archa moorthees and preparing food in the kitchen. But, he allocated various other tasks of temple management to other NB castes. He also wanted the NB SVs to be treated with equal respect. There is a document called
கோவிலொழுகு that describes who does what when. These NB SVs involved in temple activities came to be known as சாத்தாத ஐயங்கார் apparently a reference to the lack of பூனூல். There is even a recorded instance of a Brahmin SV joining the ranks of சாத்தாத ஐயங்கார் by apparently removing his பூனூல்.
This kind of progressive, and even revolutionary for the their time, thinking continued for another 100 to 150 years. However, there was some rumbling from the Vadama converts right from Ramanuja's time about the diminished focus on Varna. One glimpse of this can be seen with the objection some raised that Ramanuja's retinue included NBs and that he placed his hand on the shoulders of NB returning from bath in river Kaveri. This strain of jAti thinking must have continued as a subcurrent waiting for the arrival of Desikan. When he arrived in the scene he firmly rejected the idea that NBs can be treated as equal. He compared devout and learned NB SVs to temple cow, one may give respect to these individuals, but in the final analysis they are not Brahmin and therefore unfit to be treated as equal.
The division was firmly established. One faction was firmly committed to Varna dharma (vadakalai) and the other (thenkalai) somewhat permissive. But they didn't fight with each other openly as they do today. Under both kalais, when people joined their ranks they didn't get rid of their jAti, just that within Thenkalai tradition they were treated a little bit better. This must be the reason why most NB SVs are thenkalais.
In summary, the kalai difference is strictly doctrinal, the kalai fights in temples are about control and not doctrinal, Thenkalai Brahmins are not NB converts.
regards ...