The seventh chapter on “The Parable of a Magic City” of the Lotus Sūtra states that the Great Universal Wisdom Buddha had been the king of a country with 16 princes before entering the priesthood; when the king became a Buddha, his 16 princes awakened aspiration for Buddhahood and became novices. Meanwhile the 16 novices grew to be 16 bodhisattvas, preaching the Lotus Sūtra as their father Buddha had taught them and planting the seed of Buddhahood in all the people in the Sahā World. These 16 bodhisattvas all attained Buddhahood, the seventh chapter continues, and they became 16 Buddhas, the first of whom was Akṣobha Buddha, the ninth was Amitābha Buddha, and the sixteenth was Śākyamuni Buddha. Akṣobha Buddha has connection with the world to the east, Amitābha (Buddha of Infinite Life) is connected to the world of the west, and only Śākyamuni Buddha has a karmic relationship with this Sahā World. Each of these Buddhas is equipped with the three benefits of guidance (sowing, maturing, and harvesting) and the three virtues (of lord, master and parents), but both Akṣobha and Amitābha Buddhas are provisional Buddhas who appeared in the world to preach expedient teachings. Therefore, they have neither the three benefits nor the three virtues in the true sense of the word. In other words, their benefits and virtues are recognized only in term of their guidance of the people in their respective worlds, whereas the Eternal Buddha Śākyamuni is perfectly equipped with the three benefits and three virtues.

Ichidai Goji Keizu, Genealogical Chart of the Buddha’s Lifetime Teachings in Five Periods, Writings of Nichiren Shōnin, Doctrine 3, Page 248

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