Description of Pitrs - Verse 65-67

Those who perform sacrifices and preside over them are known as Agnisvattas. Those who adhere to their duties in virtue of their stages in life, those who closely follow the traditions, those who do not blunder in the performance of their rites with faith, those who are engaged in the holy rites till death, after being endowed with celibacy, penance, Yajna, progeny, faith, learning and charitable gifts (are also called Agnisvattas. )