[In the Senji—shō] he discussed the spread of the Lotus Sūtra during the two periods of the Perfect and Counterfeit Law and concluded that although the Lotus Sūtra was known and taught by such people as Chih-i, Miao-lo, and Dengyō Daishi they realized that the Age of the Last Law was the ideal time to spread the Lotus Sūtra.

Nichiren … explained to his listeners how fortunate they were to be born in the Age of the Last Law and to be able to hear the Lotus Sūtra. He taught that the Buddha was simply preparing the ground for this teaching; the prior periods were periods of fermentation, periods in which conditions had to develop which would allow for the emergence of the Lotus Sūtra. … [N]ichiren is making the main point of the Senji—sho. He is differentiating the past and future and stating that it is better to be born in the Age of the Last Law as common people, able to practice Lotus Sūtra Buddhism, than to have been born kings or great monks in any prior time.