Allegation: The Theme of "On Persecutions Befalling the Sage" is encouragement of the faithful in the wake of the Atsuhara Persecution. The reference to the "fundamental intention for coming forth in this world" has no connection with the so-called "Ita Mandala [Daigohonzon]," which is not mentioned in this letter at all. Taiseki-ji and SGI has used the date of this letter to back it claims for the date of the Ita Mandala. Nichiren Shonin's "fundamental intention", according to this letter was having fostered his disciples to the point where they gave up their lives for the Lotus Sutra.
Nichiren Shoshu Rebuttal: What enabled the Daishonin to fulfill his fundamental purpose behind his advent in this world? At the expense of their lives, the Atsuhara farmers showed actual proof of their solid faith in the Daishonin's teaching. The establishment of their unshakable faith meant the establishment of Nichiren Daishonin's Buddhism. In other words, by witnessing their true faith, the Daishonin could decide upon the inscription of the eternal object of worship for all humanity.
My Response: Let us look to the Kaimoku Sho and not the fairy tales of the SGI and Nichiren Shoshu for the answer to what was Nichiren Daishonin's "fundamental intention for coming forth in this world". "
The Great Teacher Chang-an interprets this story from the Nirvana Sutra in terms of the three obstacles. Observe how he does this. The fact that thewoman is called "poor" indicates that the person does not have the treasure of the Law. The fact that she is identified as a woman indicates that the person has a measure of tenderness. The "inn" signifies an impure land. The child shebears is the heart that has faith in the Lotus Sutra, or the wisdom that perceives one’s inherent Buddha nature. Being driven out of the inn by its master signifies that the person is exiled. The fact that the baby has just been born means that very little time has passed since the person began to have faith in the Lotus Sutra. The fierce wind the woman encounters is the imperial decree sentencing the person to exile. The mosquitoes, gadflies and other insects are the "many ignorant people who will curse and speak ill" of the votary of the Lotus Sutra. The fact that both mother and child are drowned indicates that, though in the end the person had his head cut off, he never renounced his faith in the Lotus Sutra. Being reborn in the Brahma heaven means being reborn in the realm of Buddhahood.
The power of karmic rewards extends to all of the Ten Worlds, even to the realm of Buddhahood. Even though one might go around killing people throughout the provinces of Japan and China, if one does not commit any of the five cardinal sins or does not slander the Law, one will not fall into the hell of incessant suffering. Yet one must go through other evil paths for a period of numerous years. Even if one observes ten thousand precepts and performs ten thousand good deeds, if one does so with a mind only half intent, one cannot be reborn in any heaven of the world of form. To be born a king in the Brahma heaven of that world, one must add the spirit of compassion to one’s karma that goes with outflows and leads one in that direction. The poor woman in the sutra passage was reborn in the Brahma heaven because of her concern for her child. Her case is different from the nature of causality that is commonly known. Chang-an offers two interpretations of it, but in the end it is nothing other than the loving kindness with which the woman cares for her child that makes the difference. Her concern concentrates on one thing just like the Buddhist practice of concentration. She thinks of nothing but her child, which is similar to Buddhist compassion. That must be why, although she created no other causes to bring it about, she was reborn in the Brahma heaven.
The path to Buddhahood is not to be found in the Kegon doctrine of the phenomenal world as created by the mind alone, in the eight negations of the Sanron sect, in the Consciousness-Only doctrine of the Hosso sect, or in the Shingon type of meditation on the five elements of the universe. Only the T’ien-t’ai doctrine of the three thousand realms in a single moment of life is the path to Buddhahood. Even in the case of this doctrine of the three thousand realms in a single moment of life, we do not possess the kind of wisdom and understanding to comprehend it fully. Nevertheless, among all the sutras preached by the Buddha during his lifetime, the Lotus Sutra alonecontains this jewel which is the doctrine of the three thousand realms in a single moment of life. The doctrines of the other sutras are merely yellow stones that appear to be jewels. They are like sand, from which you can extract no oil no matter how hard you squeeze it, or a barren woman who can never bear a child. Even a wise man cannot become a Buddha through the other sutras, but with the Lotus Sutra, even fools can plant the seeds that lead to Buddhahood. As the sutra passage I have quoted earlier puts it, "Although they do not seek emancipation, emancipation will come of itself."
Although I and my disciples may encounter various difficulties, if we do not harbor doubts in our hearts, we will as a matter of course attain Buddhahood. Do not have doubts simply because heaven does not lend you protection. Do not be discouraged because you do not enjoy an easy and secure existence in this life. This is what I have taught my disciples morning and evening, and yet they begin to harbor doubts and abandon their faith.
Foolish men are likely to forget the promises they have made when the crucial moment comes. Some of them feel pity for their wives and children and grieve at the thought of parting from them in this life. In countless births throughout many long kalpas they have had wives and children but parted from them in every existence. They have done so unwillingly and not because of their desire to pursue the way of the Buddha. Since they must part with them in any case, they should remain faithful to their belief in the Lotus Sutra and make their way to Eagle Peak, so that they may lead their wives and children there as well. "
It is clear that the Gosho, the Persecutions Befalling the Sage, is teaching that the fundamental intention laid down in the Kaimoku Sho was finally realized through the Atsuhara martyrs. Nichiren had already been inscribing Gohonzon by this time  and, as he teaches in the Real Aspect of the Gohonzon, the Gohonzon was Shakyamuni Buddha's intention, not Nichiren's. By examining the body of teachings such as those found in the Kaimoku Sho, we naturally come to an understanding of the Daishonin's teachings and intent without having to rely on the myths and fairy tales of the NST and SGI.