It is said Nikko received 'Yuiju Ichinin no Kechimyaku Sojo' (transmission of the heritage of the Law to only one person) from the founder of the Sect in accordance with Nika Sojo (documents which were believed to be addressed from Nichiren to his disciple, Nikko) in 1282.
日興は、1282年（弘安5年）の二箇相承にもとづき、宗祖から「唯授一人の血脈相承（ゆいじゅいちにんのけちみゃくそうじょう）」を受けたとされている。