Grand Master T’ien-t’ai, who is said to have directly heard the Buddha preach on Mt. Sacred Eagle, says in the Words and Phrases of the Lotus Sūtra, “The word ‘thus’ is used to show the essence of the dharma they heard from the Buddha.” Grand Master Chang-an, listened to what Grand Master T’ien-t’ai preached on the Lotus Sūtra and recorded it as the Profound Meaning of the Lotus Sūtra. He states in it, “The first preface written by Grand Master T’ien-t’ai expresses the profound mind of the Lotus Sūtra and this profound mind is nothing but the profound spirit of this sūtra.” What is referred to as the spirit of this sūtra means that the title (daimoku) is the spirit of this one. Grand Master Miao-lê says in his Commentary on the Profound Meaning of the Lotus Sūtra, “All the teachings of the Buddha stemmed from the title (daimoku) which is the spirit of letters in the Lotus Sūtra.”

Hōon-jō, Essay on Gratitude, Writings of Nichiren Shōnin, Doctrine 3, Pages 52.