The Nirvana Sūtra preaches a doctrine called “lightening the karmic retribution.” It proclaims that when a retribution accumulated from the evil karma in one’s previous lives is too heavy to be atoned for in this life, one will have to endure the suffering in hell in the future. One may, however, bear hell’s suffering in the present life instead so that one’s suffering in hell in a future life disappears instantly and one will instead be able to receive the blessings of the realm of humanity and that of heavenly beings, as well as the blessings of the Three Vehicles and attain Buddhahood after death. It was not without reason that Never Despising Bodhisattva was spoken ill of, slandered, beaten with sticks and pieces of wood, or had rubble thrown at him. His persecution in this life seems to be the consequences of his slandering the True Dharma in his previous lives. Therefore it is stated in the sūtra, “His sins have been atoned.” I believe it means that Never Despising Bodhisattva’s past sin ceased to exist through his persecution.

Tenjū Kyōju Hōmon, Lightening the Karmic Retribution, Writings of Nichiren Shōnin, Followers I, Volume 6, Page 29