World's Oldest Scriptures -- The Vedas

All this we know about the Aryans from their literature. But as writing was not known in India until about 600 B.C., how could they have had a literature? It was not in books at all; these ancient Indians stored in their memory everything they discovered and passed it on from teacher to pupil. This was called Veda, "knowledge", and the language was an early form of Sanskrit. Scholars say that such was the Aryan power of memory, in all those centuries the Vedas were not changed in any important way. Imagine what your schooling would be like if nothing could be written down! This knowledge was collected into four Vedas by a sage named Vyasa, which is just about the first name we have in Indian history.
To understand what these writings are all about we must first look at Aryan society. At the head of it stood the priests, who knew the rituals and mantras (formulas) for the sacrifice. After them came the warriors, then the artisans, farmers and merchants, and finally the common labourers. It was the priests who preserved all the higher learning; that is why they were respected throughout the centuries as the superiors of the "caste system". In the first half of the Vedas are collected their prayers, hymns and formulas used at the sacrificial fires. The Vedas are primary scriptures; all later ones, such as the Puranas, are secondary, and may be added to in the future. "God's book is never closed".