In Chapter 21, “Supernatural Powers of the Tathagatas,” Sakyamuni authorizes these Great Bodhisattvas from Underground to propagate the Lotus Sutra after his extinction. Besides, the Buddha teaches that the heart of the Sutra’s teachings should be manifested through four key dharmas: (1) all the teachings of the Tathagata, (2) all the unhindered, supernatural powers of the Tathagata, (3) all the treasury of the hidden core of the Tathagata, and (4) all the profound achievements of the Tathagata.

Nichiren interpreted the four key dharmas to be represented in the title, MYO-HO-REN-GE-KYO, or “Sutra of the Lotus Flower of the Wonderful Dharma.” Besides, he understood that in the Age of Degeneration, the Bodhisattvas from Underground will certainly appear in order to propagate the Name of the Dharma. As long as Sakyamuni was physically present, the essence of the Primal Mystery (Hommon) was present in the “one chapter and two halves.” In the evil world after his death, however, that key concept would be revealed in the five-character title of MYO-HO-REN-GE-KYO, or the “Sutra of the Lotus Flower of the Wonderful Dharma.