Mbh 13.84.2c

It was first recited to Rama, the son of Jamadagni. In former days Jamadagni's son Rama, filled with great wrath, exterminated the Kshatriyas from off the face of the earth for thrice seven times. Having subjugated the entire earth the heroic Rama of eyes like lotus-petals began to make preparations for performing a Horse-sacrifice, O king, that is praised by all Brahmanas and Kshatriyas and that is capable of granting the fruition of every wish. That sacrifice cleanses all creatures and enhances the energy and splendour of those who succeed in performing it. Endued with great energy, Rama, by the performance of that sacrifice became purified. Having, however, performed that foremost of sacrifices, the high-souled Rama failed yet to attain to perfect lightness of heart. Repairing unto Rishis conversant with every branch of learning as also the deities, Rama of Bhrigu's race questioned them. Filled with repentance and compassion, he addressed them, saying, 'Ye highly blessed ones, do ye declare that which is more cleansing still for men engaged in fierce deeds.' Thus addressed by him, those great Rishis, fully acquainted with the Vedas and the scriptures, answered him, saying, 'O Rama, guided by the authority of the Vedas, do thou honour all learned Brahmanas. Following this conduct for some time do thou once more ask the regenerate Rishis as to what should be done by thee for cleansing thyself. Follow the advice which those persons of great wisdom give.' Repairing then to Vasishtha and Agastya and Kasyapa, that delighter of the Bhrigus, endued with great energy, asked them that question, 'Ye foremost of Brahmanas, even this is the wish that has arisen in my heart. How, indeed, may I succeed in cleansing myself? By what acts and rites may this be brought about? Or, if by gifts, what is that article by giving away which this wish of mine may be accomplished?