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The loss of the northern and northwestern Kṛṣnayajurveda traditions due to the Mohammedan depredations of Northern India (aided an abetted by the predatory Anglospheric regimes) has been one the great tragedies faced by Hindudom. Hence, it is rather important to collate and restore whatever remains of these traditions, namely those belonging to the Kaṭha and Kapiṣṭhala schools, which were once dominant in the greater Panjab and Kashmir. In the 1940s, vidyābhāskara, vedāntaratna Sūryakānta, saṃskṛtācārya of the Pañjāba-viśvavidyālaya, Lavapura (modern Lahore) had collated several Kaṭha fragments that came from lost texts outside of the relatively well-preserved saṃhitā. These came from the lost brāhmaṇa and the surviving āraṇyaka, as well as the lost mantrapāṭha of the Kaṭha-s that went with the sūtra-s of Laugākṣi. Notable in this regard, were the following manuscripts that Sūryakānta found in what is today the terrorist state: 1) A Śāradā manuscript which was written in 1033 Vikrama-saṃvat, bright āṣāḍha aṣṭami (approximately June of 1111 CE) in Gilgit. Ironically, this manuscript was found in the possession of a mulla named Hafiz ar Rahman of the Panjab [footnote 1] and contained 340 folios. This was an extensive paddhati with several Kaṭha mantra-s and brāhmaṇa sections used in their late gṛhya rituals. Another Śāradā manuscript, found in the possession of the same mulla, of 180 folios contains overlapping content from brāhmaṇa and mantra material used in Kaṭha rituals. Finally, there was the D.A.V. college manuscript with two parts of 189 and 169 folios respectively that was again an extensive paddhati with overlapping material. The above Rudra-mantra-s come in the sections labeled Rudra-mantrāḥ or Śatādhyāya(Rudra)mantrāḥ and comprise their second division, coming after the Śatarudrīya. The fate of these manuscripts after the vivisection of India in 1947 CE remains unclear. In the past year, the eGangotri trust has made freely available two independent texts which span the mantra-s in question from the Raghunātha Mandira Sanskrit collection, Jammu. One is a Śāradā manuscript of the Śatādhyāya-dīkṣa and another is a print version of the Śatādhyāya produced in the 1920s by the Kashmirian brāhmaṇa-s, Tārachanda Kaulā and Keśava Bhaṭṭa. These have helped correct some problematic parts of the Sūryakānta texts.
The first part of this fragment is a rather important because is the only occurrence of a variant version of this famous incantation to Rudra found outside the Atharvaveda saṃhitā-s. The said incantation occurs as sūkta 11.2 in the AV-vulgate (often taken to be the Śaunaka saṃhita) and as sūkta 16.104 in the Paippalāda saṃhitā. In totality, the two AV versions resemble each other more closely and have a more extensive set of mantra-s. This clearly establishes that it was not a late acquisition of the Kaṭha-s from the neighboring Paippalāda-s, who were also prominent in the same region (e.g. the Kashmirian intellectual bhaṭṭa Jayanta). Two further points are notable. This text is entirely rhotacizing (e.g. arikravebhyaḥ) relative the fully or partial lambdacizing AV saṃhitā-s (AV-vul: aliklavebhyaḥ; AV-P ariklavebhyaḥ). On the other hand, it has mṛḷatam, mimicking the Ṛgveda dialect, instead of the AV mṛḍatam. Similarly, this text shows the archaism of using the RV-type dual form Bhavā-śarvā as opposed to the AV Bhavāśarvau. This was likely originally part of the Kaṭha-mantrapāṭha which went the sūtra-s of Laugākṣi.
It shares with the AV and Śāṅkhāyana-RV traditions, the conception of Rudra in his twin form — Bhava and Śarva. In the Śāṅkhāyana-śrautasūtra (4.20.1-2), Bhava and Śarva are called the sons of Rudra Mahādeva, thus presenting them as ectypes of the Aśvin-s, who are the sons of Rudra in the RV [footnote 2] and mirror the para-Vedic Skanda-Viśākha dyad who are coupled with Rudra (e.g. in gṛhya-pariśiṣṭa-1 of the Kauthuma Samaveda: oṃ rudraṃ skanda-viśākhayos tarpayāmi ।). In contrast, while Bhava and Śarva are used as epithets of Rudra in other Yajurveda traditions (e.g. Taittirīya), they are not presented as twins. This suggests that the the Kaṭha tradition developed in proximity to the locale where AV traditions original diversified in which the cult of the twins Bhava and Śarva, like that of the Greek Dioscouri, was dominant.
The second part is homologous to the equivalent section of the Aruṇa-praśna of the Taittirīya āraṇyaka, which is used in the Āruṇaketukacayana ritual, where the bricks of the citi are replaced by water-filled pots. It might have been part of an equivalent lost section of the Kaṭha brāhmaṇa. It is largely equivalent to the TA version with a few variants that we have retained due to consistency across Kaṭha manuscripts. Variants of the final mantra are found as AV-vulgate 7.87.1; AV-P 20.33.7 and Taittirīya saṃhitā 188.8.131.52; Kaṭha saṃhitā 40.5.33. The Kaṭha version is oddly formed and unmetrical both in the saṃhitā and across the prayoga manuals. Hence, we retain it as is without emendation or metrical restoration based on the other saṃhitā-s.
footnote 1: He could have descended from converted brāhmaṇa-s
footnote 2: https://manasataramgini.wordpress.com/2020/01/12/the-asvin-s-and-rudra/