You are called Pavaka, because you sanctify every thing; thing; you are called Havyavahana, because you carry the sacrificial libation of Ghee. The Vedas have all sprung from you, and therefore, you are called Jatavedas.
पावनात् पावकश्चासि वहनाद्धव्यवाहनः। वेदास्त्वदर्थं जाता वै जातवेदास्ततो ह्यसि॥