Manusmriti 11.255

11.255

abdārdham indram ity etad enasvī saptakaṃ japet
apraśastaṃ tu kṛtvāpsu māsam āsīta bhaikṣabhuk //

But he who has committed many sins, becomes pure, if he recites during a month the (four verses) addressed to Soma and Rudra, and the three verses (beginning) 'Aryaman, Varuna, and Mitra,' while he bathes in a river.