Mbh 13.125.5

"'"The celestial messenger said, 'Thou hast explained the division of the rice-balls and their consignment one after another to the three (viz., water, the spouse, and the blazing fire), together with the reasons thereof.[541] Whom does that rice-ball which is consigned to the waters reach? How does it, by being so consigned, gratify the deities and how does it rescue the Pitris? The second ball is eaten by the spouse. That has been laid down in ordinance. How do the Pitris of that man (whose spouse eats the ball) become the eaters thereof? The last ball goes into the blazing fire. How does that ball succeed in finding its way to thee, or who is he unto whom it goes? I desire to hear this,--that is, what are the ends attained by the rice-balls offered at Sraddhas when thus disposed of by being cast into the water, given to the spouse, and thrown into the blazing fire!'