Four Collections, Four Priests, One Sacrifice

The division into four is not a division of subject matter. It is a division of labour at the sacrifice, where different priests had different offices and each needed his own material. The Rig collection supplies the verses of invocation recited by the priest who calls the gods, the Sama supplies the same material set to melody for the priest who sings, and the Yajur supplies the formulas muttered by the priest who performs the physical acts of the offering. Each collection is shaped by its function, which is why the Sama is largely Rig verse arranged for chant rather than new composition.

The fourth collection sits differently. Its contents run to healing, protection, cursing, household concerns and speculation, matters at some distance from the solemn public rite, and for a long period the authoritative body was spoken of as threefold knowledge, with this collection outside it. Its acceptance as the fourth Veda was a development rather than a starting point, and the tradition preserved traces of the argument. Each collection then further divides by school, and each school carried its own recension with its own text and its own ritual manuals. Most of those schools are lost, known only by name or by citation, so what survives is a fraction of what existed and not a complete original.