Agniveśya (Agniveshya) has been directly referred to as Agni’s son in Mahābhārata (Mahabharata). He was a sage — agnestu jātaḥ sa muniḥ. He was trained in martial arts by the famous sage Agastya, and later, it appears, from the great sage Bharadvāja (Bharadwaja) as well. Bharadvāja had presented Agniveśa with āgneya astra (agneya astra) or the weapon blessed by the Fire-god, Agni. Bharadvāja’s son Droṇācārya (Dronacharya) learnt the ways of warfare from Agniveśa. He had spent many years in Agniveśa’s hermitage for learning the arts of archery and the use of weapons and armors. During this period, he had exercised utmost restraint of his senses and had led the life of a celibate novice, and his head had become all covered with dreadlocks.

However, Agniveśa was so pleased with Droṇācārya’s perseverance and efforts that he gave away āgneya astra which was given to him by Bharadvāja. Droṇācārya, empowered with āgneya astra that belonged to his father and the superb training in the means of warfare that he had received from Agniveśa, later boasted — “My master Agniveśa had learnt the art of archery from the great sage Agastya. I am proud to be his disciple” — agastasya dhanurvede śiṣyo mama guruḥ purā/ agniveśa iti khyātastasya śiṣyo’smi bhārata.

It seems that Agniveśa had received a deadly weapon called Brahmaśira (Brahmashira) from Agastya. At a later period he gave away this weapon, along with other celestial weapons, to his favorite disciple Droṇācārya. As disciples of Droṇācārya, Arjuna and Aśvaththāmā (Ashwatthama) received this weapon from Droṇacāryā in the same tradition.