Jishu, which had been written as '時衆' for a long time, was written as '時宗' for the first time in "Jishu Fujisawa Yugyo Matsuji-cho" (Note of Branch Temples of Fujisawa Yugyo-ji Temple of the Ji Sect) in 1633.
「時宗」と書かれるようになったのは、寛永10年（1633年）の『時宗藤沢遊行末寺帳』が事実上の初見である。