How can we know that the Gita hasn’t changed over the centuries?
Question: How do we know Bhagavad-gita has not changed over the centuries?
We can understand this in two ways: (i) through study of historical writings, also known as historiographical analysis (ii) through essential effects of the book.
From the point of view of historiographical analysis, the Gita is a very stable text. Sripad Shankaracharya, one of the famous commentator on the Gita, commented on the book almost fifteen hundred years ago. Although, generally speaking, there remains a possibility that a book can be interpolated, however, when some book is commented on, then the followers of that commentator preserve the book very carefully. That way a book remains preserved and possibility of any interpolation can be ruled out.
Books that are very big to be commented on, there is an increased likelihood of interpolation. For example, some of the Puranas that are very big and they do not have much commentaries in them, interpolation is much more likely. Bhagavad-gita is a small book with around seven hundred verses. Even today many people memorise the Gita, what to speak of the past when many more would memorise the Gita. If a book is not so big to be memorised it is easy to detect interpolation. Also, traditional culture was much stronger in the past than what we see today. Sacred texts are not considered so sacred these days, but even now some amount of sanctity is there. People still put hand on the Bhagavad-gita to give testimony in court. If we look further back than just fifteen hundred years ago, it is reasonable to infer that presence of a strong culture would have preserved the book.
Now let us answer this question from the point of view of effect of the book. Let us first understand what is meant by “effect of the book” with the help of an example. If we purchase a medicine, which is supposed to cure fever, how can we be certain that there was no adulteration done throughout the supply chain starting from purchase of raw material, manufacturing, and finally sales at a medical store? Before taking the medicine do we trace the root and find out where this medicine came from? No, we do not do that. We simply take the medicine and if the fever is cured, we accept that the medicine is unadulterated. Similarly, we can look at Bhagavad-gita and analyse its effect on its original student, Arjuna, and its effect on today’s practitioner.
Bhagavat-gita is a text about dharma. Gita answers the question what should we do. In order to understand what should we do, we need to understand who we are and what is our purpose. Bhagavat-gita answers these two questions also when it discusses about sadhya (the goal) and sadhan (the means to the goal).
Arjuna says in Bhagavat-gita 10.12: param brahma param dhama, pavitram paramam bhavan (“You are the Supreme Personality of Godhead, the ultimate abode, the purest, the Absolute Truth”). Here Arjuna clearly identifies Lord Krishna to be the sadhya, the goal. Later after hearing the Gita, Arjuna says in 18.73, karishye vacanam tava (“I will do whatever you want me to do”). Here Arjuna, after hearing the Gita, agrees to fight not because he is a fighter, but because Krishna wants him to fight. Arjuna’s action tells us about the sadhan, which is surrendering to the will of the Lord (maam ekam sharnam vraja, BG 18.66), also known as bhakti yoga. Therefore, as per the original student of Gita, the sadhya is Krishna and the sadhan is bhakti.
Thousands of years later, today, what is the effect we see on people after they understand Bhagavat-gita? Do they understand sadhya to be Krishna? By Srila Prabhupada’s mercy thousands of people from all over the world have accepted Krishna as the Supreme Lord or the sadhya. What about the sadhan? These people sincerely started practicing bhakti yoga. We see the same effect on today’s listener as was on Arjuna when understood Gita.
We can go through the historiographical analysis if that is our interest but that is a long laborious process. Even from historiographical analysis also Gita is a remarkably stable text. However, more important is the effect of the Gita. If Gita can guide us today also in the same way it was able to guide the original student Arjuna, it means that even today the essential effect of the Gita is available in the same way as it was available centuries ago. This is the best testimony that Gita has not changed over the centuries.