Many thanks to Suganya Anandakichenin for providing me with noteworthy additional occurrences of the stanza:
• at the beginning of the Maṇipravāla work Mānikkamālai of Periyavāccāṉ Piḷḷai (ca 13th c.), with the variant in d "tasmād brāhmaṇa-daivatam" and where the word brāhmaṇa is understood as a synonym of ācārya.
• in Vedānta Deśika's commentary (Tātparyacandrikā) on Rāmānuja’s Gītābhāṣya 18.15:
tathā 
daivādhīnaṃ jagat sarvaṃ  mantrādhīnaṃ tu daivatam |
tan mantraṃ brāhmaṇādhīnaṃ  tasmād viprā hi daivatam || (note again the variant in d)
iti
a quotation for which the editor gives in footnote the reference to Vihagendrasaṃhitā 22.15. 
I have no access to the latter text for checking the version of the stanza (see Vihagendrasaṃhitā [Vihakēntira samhitā; cutarcan̲a mantra cāstram], ed. Ā. Vīrarākavan [A. Veeraraghavan], Tanjore Sarasvati Mahal Series [Tañcāvūr Caracuvati Makāl veḷiyīṭṭu] no. 465, 2005). However, Vedānta Deśika mentions a saṃhitā with this title in his Pāñcarātrarakṣā (ed. D. Aiyangar and T. Venugopalacharya, Adyar Library Series no. 36, p. 23; cf. Gonda, Medieval Religious Literature in Sanskrit, A History of Indian Literature 2/1, 1977, p. 106) [I owe this latter reference to Ewa Dębicka-Borek]. So, even if the Vihagendra- is not an early pāñcarātra saṃhitā (not mentioned in Schrader's or Matsubara's books; I have not Smith's ones at hand), like Periyavāccāṉ Piḷḷai it should precede Vedānta Deśika by at the least more than one hundred years. 
So these sources point to the 12th century Śrīvaiṣṇava milieu for a possible origin of the stanza.

Best wishes,

Christophe 

Le 3 janv. 2020 à 17:14, Christophe Vielle via INDOLOGY <indology@list.indology.info> a écrit :

Dear list,

in reading the auto-biography of the Kerala social reformer V.T. Bhattathiripad (1896-1982) born in a Nambudiri brahmin family (My Tears, my Dreams - Kanneerum Kinaavum, New Delhi: Oxford UP, 2013, translated from the Malayalam), sprinkled with Sanskrit verses (from the author's memory) in approximative transliteration (unfortunately I have not yet the original, with correct Sanskrit, version), I come across the following śloka (p. 27, corrected):

daivādhīnaṃ jagat sarvaṃ  mantrādhīnaṃ tu daivatam |
tan mantraṃ brāhmaṇādhīnaṃ  brāhmaṇo mama daivatam ||

with the author's comment "I don't know which idiot made up this verse in Sanskrit".

From a first search for, I found the same verse in Sāyaṇa's commentary on the Vaṃśabrāhmaṇa (ed. A.C. Burnell, Mangalore, 1873), p. 2 of the bhāṣya


with the variant in d "nama [sic] devatā" and the note by Burnell: "I cannot identify this piece of insolence. It is always in the mouths of S. Indian Brahmans."

The verse is also to be found in (the same) Sāyaṇa's Subhāṣitasudhānidhi (crit. ed. K. Krishnamooorthy, Dharwar, 1968, p. 22, 5.5,  with the variant in d "daivataṃ mahat": https://archive.org/details/21subhashitasudhanidhiofsayanacarya_201908/page/n25 ), which itself relies on the earlier (13th-14th c.?) South-Indian anthology Sūktiratnahāra (ed. K. Sambasiva Sastri, TSS 141, 1938, p. 6, 5.5, with the same variant in d "daivataṃ mahat": https://archive.org/details/in.ernet.dli.2015.284105/page/n21 - https://archive.org/details/in.ernet.dli.2015.493619/page/n27 )

(unfortunately, the MSS has not reached the letter d).

Would somebody be aware of other, and especially earlier, occurrences in Sanskrit literature of this "traditional" verse (e.g. here quoted in a Tamil brahmins forum: https://www.tamilbrahmins.com/threads/temple-renovations.27311/  - note that the last pāda "brāhmaṇo mama daivatam" = also Viṣṇudharma 52.20 ed. Gruenendahl on GRETIL).

Thank you for any additional information,

With best wishes,

Christophe


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Christophe Vielle
Louvain-la-Neuve



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Christophe Vielle
Louvain-la-Neuve