While [Nichiren’s] single-practice orientation is itself open to criticism for the ease with which it can translate into dogmatic self-assertion, such observations miss the underlying logic of Nichiren’s aim. This appears to have been not to eradicate the spectrum of religious interpretations current in his day, but to undercut their bases in other traditions and assimilate them to the Lotus Sūtra. This is illustrated in the following passage:

Once they enter the great ocean of the Lotus Sūtra, the teachings preached before the Lotus are no longer shunned as provisional. It is the mysterious virtue of the great ocean of the Lotus Sūtra that, once they are encompassed in the single flavor of Namu-myōhō-renge-kyō, there is no longer any reason to refer to the distinct names “nenbutsu, ” “precepts,” “shingon, ” or “Zen.” Thus the commentary states, “When the various rivers enter the sea, they assume the same unitary salty flavor. When the various kinds of wisdom [represented by the provisional teachings] enter the true teaching, they lose their original names.

Nichiren’s teaching is no less exclusivistic for its attempt to be all-encompassing, but it should be understood as one of a number of contemporaneous attempts at subsuming all teachings, virtues, and possibilities within a single formulation. (Page 297)

As we have seen, the five characters of the daimoku are said to contain all teachings and to encompass all phenomena. They also contain the merit of all the good practices of the Buddhas, such as the six Pāramitās, and the virtues of enlightenment in which they result. However, this is not the only sense in which the daimoku is claimed to be all-inclusive. By the logic of the single-practice position, being by definition the only practice a true devotee should uphold, the daimoku is also said to produce all possible benefits. Nichiren’s teaching assimilates to the daimoku all the goods that religion in medieval Japan was thought to provide. In his various writings, faith in the Lotus is said to offer the realization of Buddhahood in this body, healing and other worldly benefits, protection of the nation, repentance or expiation of sin (sange), and birth after death in a pure land. Similarly, Nichiren’s idea of the Buddha of the Lotus Sūtra encompasses all conceptions of the Buddha that were current in his day. Śākyamuni is “our blood and flesh,” “our bones and marrow.” But at the same time he is ruler of the world, compassionate parent, and wise teacher to all beings. Nichiren’s use of hongaku ideas is also assimilated to this polemic of the all-inclusiveness of the Lotus Sūtra. The Lotus is presented as the only sūtra to reveal that the enlightened state of the Buddha and the nine realms of deluded beings are mutually encompassing and originally inherent; this is what makes the Lotus uniquely true and superior. (Page 296)

[I]n Nichiren’s thought, enlightenment, or salvation, depends not on multiple factors but on one condition only—faith in the Lotus Sūtra, which is inseparable from the chanting of the daimoku. Anyone who chants the daimoku, man or woman, cleric or lay person, foolish or wise, realizes enlightenment. Correspondingly, there is but one single error or evil that can obstruct this enlightenment: “slander of the Dharma,” or willful disbelief in the sūtra. To discard the Lotus Sūtra, Nichiren writes, “exceeds even the sin of killing one’s parents a thousand or ten thousand times, or of shedding the blood of the Buddhas in the ten directions.” The modality of Nichiren’s doctrine on this point appears at first absolutely either/or: “Disbelief is the cause of the icchantika and of slander of the Dharma, while faith is the cause of wisdom (prajn͂ā) and corresponds to the stage of verbal identity.” So powerful is faith in the Lotus that no worldly evil can ever counteract it and pull the practitioner down into the evil paths. Conversely, slander of the Lotus Sūtra is so great an evil that no accumulation of worldly good deeds can ever offset it or save one who commits it from the Avīci Hell. On a deeper level, however, the dichotomy is dissolved, for even to slander the Lotus Sūtra is to form a connection with it. Thus in Nichiren’s view, even if one’s practice of shakubuku should arouse the enmity of others and cause them to slander the Lotus Sūtra, because it nonetheless allows them to form a “reverse connection” with the sūtra, that is far preferable to their having no connection at all. Once the retribution of their slander is expiated, they will, by virtue of that connection, encounter the sūtra again and attain Buddhahood. (Page 295-296)

In Nichiren’s view, enlightenment is realized in the moment of practice. This enlightenment is a timeless state, in which original cause (the nine realms) and original effect (Buddhahood) exist simultaneously and is ever accessible in the act of chanting the daimoku. The practitioner does not progressively expunge defilements or accumulate merit with a view to reaching eventual enlightenment, because all merit is inherent in the daimoku and “naturally transferred” to the person who embraces it. As in other Buddhist teachings of this time that assert direct and full accessibility of salvation or enlightenment in the present moment, Nichiren’s doctrine nevertheless includes a discourse about the importance of continuing one’s practice or further deepening one’s faith. (Page 295)

[The moment of “embracing” the Lotus Sūtra as conceived in Nichiren’s thought] is a moment of intersection between the present time and the timeless realm of enlightenment, in which the Buddha, the practitioner, and the practitioner’s outer world are all identified. It is described as the “three thousand realms in one thought-moment,” which is implicit in the practitioner as the ontological basis of enlightenment, embodied in the daimoku and the object of worship, accessed in the act of faith and chanting, and manifested outwardly in the transformation of the world. This reality is both inherent in and mediated by the five characters myōhō-renge-kyō conferred by the original Śākyamuni Buddha upon the people of the Final Dharma age and is accessible in no other way. This understanding of the Lotus Sūtra as the sole vehicle of realizing Buddhahood underlies Nichiren’s mandate to uphold it “without begrudging bodily life.” It also enabled him and his followers to challenge the authority of established religious institutions and to define themselves as the unique possessors of truth. (Page 294-295)