Mbh 12.272.3b

Then the presiding goddess of the solar disc, viz., Savitri, came to that sacrifice in her own embodied form and insisted upon that Brahmana in doing what he desired by that deer to do. Unto that goddess, however, who thus insisted, the Brahmana replied, saying, "I shall not slay this deer who lives with me in this same neighbourhood."[1288] Thus addressed by the Brahmana, the goddess Savitri desisted and entered the sacrificial fire from desire of surveying the nether world, and wishing to avoid the sight of (other) defects in that sacrifice.[1289] The deer, then, with joined hands, once more begged of Satya (to be cut in pieces and poured into the sacrificial fire). Satya, however, embraced him in friendship and dismissed him, saying, "Go!"[1290] At this, the deer seemed to leave that place. But after he had gone eight steps he returned, and said, "Verily, do thou slay me. Truly do I say, slain by thee I am sure to attain to a righteous end. I give thee (spiritual) vision. Behold the celestial Apsaras and the beautiful vehicles of the high-souled Gandharvas." Beholding (that sight) for a protracted space of time, with longing eyes, and seeing the deer (solicitous of sacrifice), and thinking that residence in heaven is attainable by only slaughter, he approved (of the counsels the deer had given). It was Dharma himself who had become a deer that lived in those woods for many years. (Seeing the Brahmana tempted by the prospect he beheld), Dharma provided for his salvation and counselled him, saying, "This (viz., slaughter of living creatures) is not conformable to the ordinances about Sacrifices."[1291] The penances, which had been of very large measure, of that Brahmana whose mind had entertained the desire of slaying the deer, diminished greatly in consequence of that thought itself. The injuring of living creatures, therefore, forms no part of sacrifice.