The veads at the time of Buddha was not Rig, Yaju, Sama and Atharvana. The four vedas are four noble truths at the time of Buddha. The fist three vedas (noble truths) can be codified and fourth one is called experiencial Truth, which can not be codified. This is what Buddha taught as a four Noble Truth. The Ambatta Bamano (Not Brahman), who had good knowledge in Three Vedas (Three Noble Truths) was countered by Buddha, because at the time of Buddha it was not available with other teachers. It was the Buddha who taught the fourth noble Truth the fourth Vedas (Knowledge). Let us not confuse the vedas of Buddha time with vedas of present Brahmans. There was no rig, yajur, sama and adharvana vedas at the time of Buddha. Even this Brahamanisl vedas are not Sanskrit but different language similar to Pali and Sanskrit. It is good question that why Sanskrit and Tamil were developed by Buddhists. The answer is that the new languages were developed, due to cultural and political changes in India after 1000 years of Buddha and Buddhist also started writing in Sanskrit and Tamil. If the Sanskrit and Tamil scholars say Sanskrit and Tamil were the ruling languages before or at the time or after 1000 years of Buddha, why these rulers never inscribed any document for so many years. Why we have only Tamil and Sanskrit inscriptions after 4 AD. This shows that these two languages were not existed before Buddha, at the time of Buddha and after 1000 years of Buddha....Ask all Tamil and Sanskrit scholars to come out with archaeological evidences to prove their existences.,