Mbh 13.107.2a

"'Bhishma said, "Listen, O Yudhishthira! Those ordinances that I have told thee of,--those, viz., that were first promulgated by the great Rishi Angiras, and that have reference to meritorious fasts for their soul,--are regarded as equal to Sacrifices (in respect of the fruits they bring about both here and hereafter). That man who takes one meal in the forenoon and one at night, without taking any food or drink during the interval, and who observes this regulation for a period of six years in succession, abstaining all the while from injuring any creature and regularly pouring libations on his sacred fire every day, attains, without doubt, to success. Such a man acquires hereafter a car of the complexion of heated gold, and attains to a residence, for millions of years, in the region of Prajapati, in the company of celestial damsels, that ever echoes with the sound of music and dance, and blazes with the effulgence of fire. He who passes three years, confining himself every day to one meal and abstaining all the while from congress with any other woman save his own wedded wife, attains to the merit of the Agnishtoma sacrifice. Such a man is regarded as having performed a Sacrifice, with plenty of gifts in gold, that is dear to Vasava himself. By practising truthfulness of speech, making gifts, reverencing the Brahmanas, avoiding malice, becoming forgiving and self-restrained, and conquering wrath, a man attains to the highest end. Riding on a car of the complexion of white clouds that is drawn by swans, he lives, for millions and million of years, in the company of Apsaras. Fasting for a whole day and eating only one meal on the second day, he who pours libations upon his sacred fire for the period of a whole year,--verily, he who observes such a fast and attends every day to his fire and rises every day from bed before sunrise, attains to the merit of the Agnishtoma sacrifice. Such a man acquires a car drawn by swans and cranes.