The Brahmanists have always regarded Sanskrit, as the Mother of Languages. As a matter of fact, this will be echoed in many of the Hindu bunch from Modern India. Latest to join in the Bandwagon, is the Tamil Dravidian nationalists, who claim Tamil to be the progenitor of all langagues. Even Though, no Indian Language or for that matter any other language, can truly claim as being the original Proto-Language of the World.
The existence of such a hypothetical Proto-World Language is itself contested. I prefer to view as Languages originally emerging as independant from each other, later influencing each other as different cultures spread around the cloud.
It is not surprising for the Brahmanists to claim the Vedic language as the Mother of All Languages. For according to Vaidikas, Vedas are Apauruṣeya (Not [authored] by Men). It was heard by the Rishis, who were just instruments for writing the cosmic sound that they heard. Vedas are also considered as Anādi (Without Begninning). So for the everlasting and supreme Vedas to be supramundane, the language in which it is composed of is also deemed to be supramundane and perfect. It was language of the gods.
Now, coming to the Shramanic religions namely Buddhism and Jainism. They started out with the vernacular prakrita languages. They were more inclined to use the language of the masses to spread their teachings. In fact, many of the initial literature in the Indian regional language were produced by the Shramanas. At one instance, the Buddha is said to have explicitly forbidden his teachings to be Versified in Vedic Language (Chandas), but to be taught in the language of the masses. But as irony befalls, the Shramanas themselves fell into the same trap as their Vedic counterparts. They began considering their own version of liturgical Prakrit as the original source language !
One interesting interesting to note that, the Shramanas considered Prakrit as the source of Sanskrit, not vice versa. The popular view is that Prakrit, is the corrupted version of Sanskrit. The Shramanas however reverse the stand saying, Sanskrit is the refined version of Prakrit.
Ardha Magadhi Prakrit of the Jainas
Lets begin with the naked Nigranthas.. 🙂 The liturgical language of the Jainas is Ardha Magadhi [Though at a very late stage, they did switch to Sanskrit, but still their ancient liturgical texts were still in Ardha Magadhi]. Infact, their usage of Prakrit continued, even after majority of the Buddhist sects began to adapt Sanskrit [or at the least Prakritic Sanskrit a.k.a Buddhist Hybrid Sanskrit]. The Jainas use of Prakrit mantra and verses for chanting and rituals were criticized by the Brahamanists.
namaṇa nantiyuṅ karuma vīraṉun நமண நந்தியும் கரும வீரனுந்
taruma cēṉaṉu meṉṟivar தரும சேனனு மென்றிவர்
kumaṇaṉ māmalaik kuṉṟu pōlniṉṟu குமணன் மாமலைக் குன்று போல்நின்று
taṅkaḷ kūṟaiyoṉ ṟiṉṟiyē தங்கள் கூறையொன் றின்றியே
ñamaṇa ñāñaṇa ñāṇa ñōṇameṉ ஞமண ஞாஞண ஞாண ஞோணமென்
ṟōti yāraiyu nāṇilā றோடி யாரையு நாணிலா
amaṇa rāṟpaḻip puṭaiya rōnamak அமண ராற்பழிப் புடைய ரோநமக்
kaṭika ḷākiya vaṭikaḷē. கடிக ளாகிய வடிகளே
Those Jainas with names such as Namana Nandi, Karma Vira, Dharmasena standing like [insignificant] hills near Mountains, being naked chant Mantras like “ñamaṇa ñāñaṇa ñāṇa ñōṇa” [Meaningless play of letters using the nasals, to mock the Prakrit usage of Jainas] , without any shame in anyones presence. Can our lord Shiva be the object of contempt of such Jainas ?
Here we can see that the Tamil Shaivaite saint makes a mockery of the the heretic Jainas’ usage of Ardha Magadhi [Prakrit languages tend to use nasal sounds more].
Even in several other verses, the Nayanmars criticize the Jainas for using the corrupted language instead of the perfect Language of the Agamas [i.e Sanskrit]
The Jainas had no reasons to crouch, ofcourse. For according to them, Ardha Magadhi was the divine language, the Original language of all. The Language spoken by Mahavira, was also spoken by [Jaina] gods and goddesses. It is thus said in the Jainas’ Aupapatika Sutra ,
With a voice that extends over a yojana, Lord Mahavira speaks in the Ardha-Magadhi language, a speech which is in accordance with all languages. That Ardha-Magadhi language changes into the own language of all those, both aryas and non-aryas.
bhagavam mahāvīre […] savvabhāsāṇugāmiṇīe sarassaīe joyaṇanīhāriṇā sareṇaṁ addhamāgahāe bhāsāe bhāsai […] sā vi ya ṇaṁ addhamāgahā bhāsā tesiṁ savvesiṁ āriyam aṇāriyāṇaṁ appaṇo sabhāsāe pariṇāmeṇaṁ pariṇamai
A 11th century Jain Author, goes to the extent of considering Prakrit as the source of Sanskrit ! He states,
[…] [Prakrit] is said to be a language easy to understand for children and women, the origin of all languages. Like the water released by a cloud, it has but one form, yet, once differences have entered because of the difference between regions and because of beautification, it acquires the later distinctions between Sanskrit and the other languages. […]
[…]bāla mahilādi subodhaṁ sakala bhāṣāni bandhanabhūtaṁ vacanam ucyate | meghanirmuktajalam ivaikasvarūpaṁ tad eva ca deśaviśeṣāt saṁskārakaraṇāc ca samāsāditaviśeṣaṁ sat saṁskṛtādyuttaravibhedān āpnoti |[…]
Therefore, its quite clear that the Jainas consider their Prakrit Ardha Magadhi as the original language of all. All languages have evolved from Ardha Magadhi, according to them.
Magadhi [Pali] Prakrit of the Thervadin Buddhists
Of all the Buddhists Traditions, Theravada was the only sect to preserve the usage of Magadhi Prakrit in its literature. [The term “Pali” was traditionally used for denoting the Texts in the language, the language is itself referred to as Magadhi in Theravadin literature]. Even though Theravada is prevalent only outside India, the usage of Pali is still strong among the native Buddhists. This serves as the strong example for the bonding between the Magadhi Language & Theravada.
Similar to the Jainas, the Theravadins also held the view that their language is the most natural language and original language.
The fifth century Visuddhimagga by Buddhaghosa declares:
Magadhi is the root of all dialects, which was spoken by Brahmas, by men before the present kalpa, by those who had neither heard nor uttered human accent, and also by supreme Buddhas
sā māgadhī mūla bhāsā nārā yā yādi kappikā
brahmānochassutālāpā sambuddhā ehāpi bāsare
The Atthagatha (commentary) of Abhidhamma Vibhanga, states the below as the view of the Buddha Bhikshu Tissadatta Thera:
If a child, born of a Damila [Tamil] mother, and an Andhaka [Telugu] father, should first hear his mother speak, he would speak the Damila language ; but if he should first hear his father speak, he would speak the Andhaka language. If however he should not hear them both, he would speak the Magadhl If, again, a person in an uninhabited forest, in which no speech (is heard), should intuitively attempt to articulate words, he would speak the very Magadhi.
It predominates in all regions (such as) Hell; the animal kingdom; the Preta sphere ; the human world ; and the world of the devas. The rest of the eighteen languages—Otta, Kirata, Andhaka, Yonaka, Damila, etc., undergo changes —but the Magadhi does not, which alone is unchangeable, and is said to be the speech of Brahmans and Ariyas.
Even Buddha, who rendered his tipitaka words into texts, did so by means of the very Magadhi ; and why ? Because by doing so it (was) easy to acquire their (true) significations. Moreover, the sense of the words of Buddha which are rendered into doctrines by means of the Magadhi language, is conceived in hundreds and thousands of ways by those who have attained the patisambhida, so soon as they reach the ear, or the instant the ear comes in contact with them ; but discourses rendered into other languages are acquired with much difficulty.
The view that Pali is immutable is so Sanskrit-like. I have heard many Sanskrit enthusiasts claim that Sanskrit has never undergone any change and pristine without any modification and alterations, unlike other regional languages and hence perfect. I don’t know why perfect languages should never change. I am of the belief, any thing natural should under go change and evolve.
This view got quote developed, the 11th century Grammar Treatise Mohavicchedani states,
It (i.e. Magadhi) was first predominant in the hells and in the world of men and that of the gods. And afterwards the regional languages such as Andhaka, Yonaka, Damila, etc., as well as the eighteen great languages, Sanskrit, etc., arose out of it.
sā va apāyesuu manusse devaloke c’eva paṭhamam ussannā | pacchā ca tato andhaka yonaka damiḽādi desabhāsā c’eva sakkaṭadi aṭṭhārasa mahābhāsā ca nibattā |
As the grand finale, here to the view converges to considering Pali as the source language of all. One interesting point to note that it considers the Greek Language (Yonaka) as being born from Pali !
Buddhist Sanskrit of Mahayana
Sanskrit, or to be precise Buddhist Hybrid Sanskrit is the liturgical language of Mahayana Buddhism. In fact, at all the Sutras and Shastra of Mahayana are completely in Sanskrit. Buddhist Hybrid Sanskrit is sort of a Prakritized Sanskrit. It is a unique Sanskrit variant with lots of Prakritic elements and imperfections (in a Paninian context), what one may consider as a Vernacular Sanskrit.
Though Mahayana itself doesn’t attribute any special status to the Sanskrit language. Johannes  suggests thats some Buddhists might have considered that Buddhist Hybrid Sanskrit as the original source language. Well, I don’t actually agree with it. As the author notes, Mahayanists didn’t seem to consider their Sanskrit different from the Sanskrit of the Brahmanists. It makes no sense for them to claim their Sanskrit was the source for the Brahmanical Sanskrit. Also, at one point of time, they completely switched from their hybrid Sanskrit to Classical Sanskrit.
1. Buddhist Hybrid Sanskrit : The Original Language, Johannes Bronkhorst
2. Introduction to Kachchayana’s Grammar of the Pali Language, James D’Alwis
3. Sanskrit and Reality: The Buddhist Contribution, Johannes Bronkhorst