Variation in Reading

As far as 'mantra' (Vedic, tantric, bIjAkshar etc.) is concerned there should not be any change in letters or even in svara. Because change of svara change the meaning. For example, in यथेन्द्रशत्रुर्वर्धस्व​ svara has been wrongly pronounced, so the negative has happened. In tantric mantra or BijAkshara also there should not be any change even a minute change. 

However, in common language (laukika bhasha) there is no such restriction. As far as possible one must try to recite without variations. In olden days, even svara etc., were in practice in laukika samkrita also. Gradually they are disappeared and not in use now except 'hrasva' and 'dirgha' ('pluta' is also in use rarely).

Some shlokas have 'mantras' being hidden in shlokas. Such shlokas are to be recited as got from the elders as 'upadesha'. Some believe that mantras hidden in shlokas are to be recited as it is written by the writer. However, the purpose of writing shlokas interwoven with mantras is to enable all the persons who are deprived of reciting mantrs. Hence, the writers of such shlokas generally take care that even if slight variation is there, it would not affect the mantra or the reciter adversely.

For example, Ramayana is considered as the representation of 'gayatri mantra' (representing each letter with one thousand shlokas). In such works, the variations would not affect as long as the meaning remains unchanged entirely against the spirit of context and meaning.

However, in such situation and also in the case of mantras as well as such 'upadesha granthas' (the texts that are to be got from a teacher or elder who got it through a tradition), the 'uadeshaka' (who imparts mantras or texts) is treated as an authority. As Ramayana being one of the texts to be got from a teacher or upadeshaka duly observing the laid down formalities, the version as of the text as it is got from is considered as 'prAmANika'. However, for the purpose research one is free to study the variations of readings as the purpose is neither sacred nor parAyaNa. 

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