Chapter 13, Encouragement for Keeping This Sūtra, opens with Medicine-King Bodhisattva-mahāsattva and Great-Eloquence Bodhisattva-mahāsattva, together with their twenty-thousand attendants who were also Bodhisattvas, vowing to the Buddha that they will keep, read, recite and expound this sūtra in the difficult Sahā world after the Buddha’s extinction.

The Buddha does not reply.

Then after the arhats and śrāvakas and the Buddha’s step-mother and former wife all offer to teach the dharma in other lands outside the Sahā world, the Buddha silently looks “at the eighty billion nayuta Bodhisattva-mahāsattvas. These Bodhisattvas had already reached the stage of avaivartika, turned the irrevocable wheel of the Dharma, and obtained dhārāṇis.” These Bodhisattvas are waiting for the Buddha to command them to keep and expound the Lotus Sūtra.

The Buddha remains silent.

This has always puzzled me. These Bodhisattvas, unlike those in Chapter 15, are not identified as having come from other worlds. Are the “eighty billion nayuta Bodhisattva-mahāsattvas” of Chapter 13 a subset of the “Bodhisattva-mahāsattvas, more than eight times the number of the sands of the River Ganges, who had come from the other worlds” in Chapter 15?

I’ve found an answer to my puzzlement in Two Buddhas Seated Side by Side, although it is hidden behind misleading shorthand in the book.

In the post Bodhisattvas from Other Worlds, I discuss the book’s suggestion that all of the Bodhisattvas who volunteer at the start of Chapter 13 “have arrived from other worlds.”

I posted on the Nichiren Shu group on Facebook the question, “With the exception of Maitreya, are all of the great bodhisattvas listed in Chapter 1, Introductory, from other worlds?”

In response, Michael McCormick said: “As far as I can tell, yes, the bodhisattva’s whose names I am familiar with in that opening passage are bodhisattvas who are of a more cosmic nature and two of them, Avalokitesvara and Mahasthamaprapta are particularly associated as attendants of Amitabha Buddha. I think the idea is that the only bodhisattva officially associated with this particular world is Maitreya Bodhisattva. The Lotus Sutra, being a relatively early Mahayana sutra, is taking the assumed cosmology and personnel of the teachings found in the Agamas and Pali canon and spinning it.”

But I believe the answer is more nuanced, and that nuance is provided by Jacqueline Stone’s explanation of how Nichiren saw the transmission of the Lotus Sūtra.

Chapters Twenty-Three, Twenty-Four, and Twenty-Five describe how specific bodhisattvas display their powers in the world to benefit sentient beings. … From Nichiren’s standpoint, the bodhisattvas appearing in these chapters had received only the general transmission described in the “Entrustment” chapter. Either they had come from other worlds, or they were followers of Śākyamuni in his provisional guise as the Buddha of the trace teaching or shakumon portion of the sūtra. Thus, their work was chiefly confined to the True and Semblance Dharma ages.

Two Buddhas, p236

It is Nichiren’s explanation that “[the Bodhisattvas] had come from other worlds, or they were followers of Śākyamuni in his provisional guise as the Buddha of the trace teaching” that explains why the Buddha does not answer the Bodhisattvas who volunteer to spread the Lotus Sūtra in Chapter 13.

Stone quotes Nichiren’s letter “Kashaku hōbō metsuazai shō” to explain:

As for the five characters Myōhō-renge-kyō: Śākyamuni Buddha not only kept them secret during his first forty-some years of teaching, but also refrained from speaking of them even in the trace teaching, the first fourteen chapters of the Lotus Sūtra. Not until the “Lifespan” chapter did he reveal the two characters renge, which [represent the five characters and] indicate the original effect and original cause [of the Buddha’s enlightenment]. The Buddha did not entrust these five characters to Mañjuśrī, Samantabhadra, Maitreya, Bhaiṣajyarāja, or any other such bodhisattvas. Instead he summoned forth from the great earth of Tranquil Light the bodhisattvas Viśiṣṭacāritra, Anantacāritra, Vlśuddhacāritra, and Supratiṣṭhitacāritra along with their followers and transmitted the five characters to them.

Two Buddhas, p219-220

To shorthand this by saying — as the book does repeatedly — these Bodhisattvas are all from other worlds, distracts the reader from the distinction between the trace teaching and the origin teaching and the significance of the transmission of Namu Myōhō-renge-kyō to the Bodhisattvas who have been the Buddha’s students since the beginningless past.