Matsyapurana 77.15

77.15

śarkarāsaptamī ceyaṃ vājimedhaphalapradā
sarvaduṣṭapraśamanī putrapautrapravardhinī //

This Śarkarâ Saptamî is said to give the same benefit as Aśvamedha sacrifice. It removes all diseases and makes the sons and the grandsons thrive. One who observes this fast with unflinching devotion, gets bliss. He passes his days for one Kalpa in heaven, and then attains emancipation. One who hears, listens, or reads about this, goes to the region of the Sun. One who advises others to observe this ordinance, is also venerated by Devas and Heavenly damsels, and passes his days in heaven.—15-17.