Suta Goswami said, “O learned brahmanas, long ago Lord Sri Krishna, the Supreme Personality of Godhead, explained the auspicious glories of Sri Ekadasi and the rules and regulations governing each observance of fasting on that holy day. O best of the brahmins, whosoever hears about the origins and glories of these sacred fasts on the Ekadasi days goes directly to the abode of Lord Vishnu after enjoying many different kinds of happiness in this material world.
“Arjuna, the son of Prithaa, asked the Lord, ‘O Janardana, what are the pious benefits of complete fasting, eating only supper, or eating but once at midday on Ekadasi, and what are the regulations for observing the various Ekadasi days? Kindly narrate all this to me’.
“‘The Supreme Lord Krishna replied, ‘O Arjuna, in the beginning of winter (northern hemisphere), on the Ekadasi that occurs during the dark fortnight of the month of Margasirsha (November-December), a novice should begin his practice of observing a fast on Ekadasi. On Dasami, the day before Ekadasi, he should clean his teeth nicely. Then during the eight portion of Dasami, just as the Sun is about to set, he should eat supper.
” ‘The next morning the devotee should make a vow, according to the rules and regulations, to observe fasting. At midday he should bathe properly in a river, lake or small pond. A bath in a river is most purifying, thsat taken in a lake is less so, and a bath in a small pond is the least purifying. If neither a river, lake nor pond is accessible, he may bathe with well-water.