Grand Master Miao-lê states in his Summary of the Great Concentration and Insight:

“The theoretical study and the spiritual contemplation of the T’ien-t’ai School is founded on the thoughts of Nāgārjuna. Since Zen Master Hui-wen in the Northern Chi Dynasty merely presented the ‘three wisdoms and threefold contemplation,’ the correct wisdom has been attained by meditation of the Lotus Sūtra, both theoretical study and spiritual contemplation have been widely discussed, and the content of the spiritual contemplation has been well arranged since the time of Nan-yüeh and T’ien-t’ai. If a person wants to practice the spiritual contemplation according to the Lotus Sūtra, he should decide the content of practice after establishing the clear answer to the issues on the provisional and true teachings, and on the essential and theoretical sections. Since the Lotus Sūtra is the sole scripture worthy of being called ‘Wonderful,’ the way of the spiritual contemplation should be established according to this sūtra. ‘Five expedients’ as preparatory practice and the ten-stage, ten-objective way of observing mind are indeed the perfect and sudden (Tendai) meditation based entirely on the Lotus Sūtra. Therefore, the perfect and sudden meditation is merely another name of meditation on the Lotus Sūtra (since it is the way of practicing the spiritual contemplation based on the truth of the Lotus Sūtra).”

Risshō Kanjō, A Treatise on Establishing the Right Way of Meditation, Writings of Nichiren Shōnin, Doctrine 2, Page 221

In such sūtras as the Amitābha Sūtra — preached during the 40 years or so before the Lotus Sūtra — the Buddha said to Śāriputra, “When one chants the name of Amitābha Buddha a million times in seven days one will inevitably be reborn in the Pure Land of Utmost Bliss.” However, upon expounding the Lotus Sūtra later, the Buddha declared, “No truth has been revealed in those pre-Lotus sūtras.” Therefore, all the scriptures of Buddhism preached before the Lotus Sūtra became meaningless, like hot water boiled for seven days but then thrown into the ocean.

Sennichi-ama Gohenji, A Reply to Sennichi-ama, Writings of Nichiren Shōnin, Volume 7, Followers II, Pages 160

I myself may be able to endure attacks with sticks and pieces of wood, withstand rubbles and debris thrown at me, vilification, and persecution by the ruler of a country, but how can lay believers who have a wife and children and no knowledge of Buddhism bear these difficulties? Wouldn’t it have been better instead for such people not to have believed in the Lotus Sūtra? I have been feeling sorry for you thinking that if you couldn’t carry through your faith, which is for temporary comfort, you would be mocked and ridiculed. However, it was wonderful that you showed the steadfastness in your faith throughout numerous persecutions including two banishments. Though you were threatened by your lord, you wrote this written pledge swearing to carry though your faith in the Lotus Sūtra even at the cost of fiefs in two places. Words cannot describe your commendable aspiration.

Shijō Kingo-dono Gohenji, Response to Lord Shijō Kingo, Writings of Nichiren Shōnin, Followers I, Volume 6, Page 142

According to Buddhist scriptures, the world goes through four kalpa (periods of construction, continuance, destruction, and emptiness), each of which consists of 20 small kalpa. In the period of continuance, the average human longevity increases by a year per century from 10 years until it reaches the maximum human longevity of 84,000 years. Thereafter the human life grows shorter by a year per century until it reaches the minimum average human life span of 10 years. Now, Śākyamuni Buddha was born to this world during the ninth small kalpa, within the kalpa of continuance, when the human life span was decreasing to 100 years. The fifty years of Śākyamuni’s appearance in this world, the 2,000-year period of Ages of the True Dharma and the Semblance Dharma, and the 10,000 years of the Latter Age of Degeneration are all included in this period, during which human longevity decreases from 100 years to the minimum of 10 years. It includes two periods in which the Lotus Sūtra flourishes: the last eight years of Śākyamuni Buddha and the first 500 years of the Latter Age of Degeneration after His extinction. Grand Masters T’ien-t’ai, Miao-lê and Dengyō missed the preaching of the Lotus Sūtra by the Buddha, nor were they able to be born in the Latter Age after His death. Regretting their misfortune for being born in between the two occasions, those grand masters made the statements cited above, wishing to have been born in the Latter Age.

This is like Hermit Asita’s lament. Seeing the birth of Prince Siddhartha, the Indian hermit deplored: “Being over ninety years old, I will not be able to live long enough to see the Prince attain Buddhahood in this world. Since I will be reborn in the realm of non-form, I will not be able to attend Śākyamuni’s preachings for fifty years in this world. Nor will I be able to be reborn after His death in the Age of the True Dharma, the Semblance Dharma, or the Latter Age of Degeneration.”

Those who have aspiration for enlightenment should be glad to see and hear these comments. Those who care for future lives should rather be born as common people today in the Latter Age than great kings during the 2,000-year period after the death of Śākyamuni Buddha, the Age of the True Dharma and that of the Semblance Dharma. How could they not believe in this? They should rather be suffering from leprosy in the Latter Age reciting “Namu Myōhō Renge Kyō (Homage to the Lotus Sūtra )” than to be the revered chief abbot of the Enryakuji Temple, grand temple of the Tendai School of Buddhism, during the Age of the Semblance Dharma. Emperor Wu of Liang in ancient China prayed: “I would rather be Devadatta, who sank to the worst Hell of Incessant Suffering but who eventually was able to attain Buddhahood through the Lotus Sūtra, than be Hermit Udraka-rāmaputra, who was able to be born in heaven but never succeeded in attaining Buddhahood.”

Senji-shō, Selecting the Right time: A Tract by Nichiren, the Buddha’s Disciple, Writings of Nichiren Shōnin, Doctrine 1, Page 195-196

The scriptural passage declaring that the Lotus Sūtra is the supreme sūtra of all the Buddhist scriptures which had been preached, are being preached, and will be preached, can hardly be refuted even by the Buddha. Much less can any inferior commentator, teacher, or king refute it with his authority? The King of the Brahma Heaven, Indra, sun and moon, and the Four Heavenly Kings all hear this statement in the Lotus Sūtra and wrote it down on their palaces.

Zui-jii Gosho, The Sūtra Preached in Accordance to [the Buddha’s] Own Mind, Writings of Nichiren Shōnin, Faith and Practice, Volume 4, Page 160

[L]ooking at the Lotus Sūtra, we find that the Buddha says, “Many people hate it (the Lotus Sūtra) with jealousy even in My lifetime. Needless to say, more people will do so after My extinction” in the “Teacher of the Dharma” chapter, and “In order to spread the Lotus Sūtra for a long time in this world” in the “Appearance of the Stupa of Treasures” chapter. Considering these statements, the Lotus Sūtra is expounded for those of us living in the Latter Age of Degeneration. Therefore, referring to this period, Grand Master T’ien-t’ai says, “Up to the fifth 500-year period after the Buddha’s extinction, people receive merit of the Wonderful Dharma afar.” Grand Master Dengyō also speaks of this period, “The Ages of the True Dharma and the Semblance Dharma have almost passed, and the Latter Age of Degeneration is shortly coming.” The Latter Age of Degeneration is coming shortly means that the time when he lived was not the time for the Lotus Sūtra to spread, but the Latter Age of Degeneration is.

Hokke Shuyō Shō, Treatise on the Essence of the Lotus Sūtra, Writings of Nichiren Shōnin, Doctrine 2, Page 214

Fascicle four of the Annotations on the Great Concentration and Insight says: “Long ago in the great country Bima, a fox pursued by a lion tried to escape but fell into a dry well. The lion leapt over the well and ran on, but when the fox tried to climb out it couldn’t because the well was too deep. Many days passed and the fox was close to starving to death. At that time the fox cried out: “Woe is me! I am going to die miserably in this dry well. All things are impermanent. It would have been better if the lion had eaten me. Hail all the Buddhas of the worlds of the ten directions, with your wisdom see that my heart is pure and precious.”

At that time, the god Indra heard the fox’s cry and came down himself to lift the fox from the well and ask it to teach the Dharma. “This is all wrong,” said the fox. “The disciple is on top and the teacher is on the bottom.” All in the heavens laughed to hear this. When Indra, acknowledging that the fox was correct, nevertheless sat at his feet and asked him to preach, the fox said, “This is all wrong. It is not right for disciple and teacher to sit down together.” Thereupon Indra took all the heavenly robes and piled them up to make a tall seat for the fox, and again asked him to preach the Dharma. The fox said: “There are those who rejoice to live and hate death. There are those who rejoice to die and hate life.” Ignorant people are ignorant regarding future lives and so they hope to live and hate death. Good people know the truth of the workings of karma and retribution and so they hope to die and hate life. Indra learned this and followed the fox as his teacher. The Grand Master T’ien-t’ai said: “The Young Ascetic in the Snow Mountains offered himself to a demon to gain half a verse, Indra revered an animal and made him his teacher. No one discards gold because the purse stinks.” No matter how humble, if someone knows the True Dharma, you must not look down on them. Fascicle 8 of the Lotus Sūtra says: “Those who, upon seeing the keeper of this sūtra, blame him justly or unjustly, will suffer from white leprosy in their present life.” This means that if one accuses the practicer of the Lotus Sūtra of faults, whether one is justified or not, one will contract white leprosy in this life and in the next life will fall into the Hell of Incessant Suffering.

Minobu-san Gosho, Mt. Minobu Letter, Writings of Nichiren Shōnin, Volume 5, Page 128

Except for bodhisattvas such as Superior Practice and Limitless Practice, highest-ranking leaders of the bodhisattvas who emerged from the earth, no one is allowed to appear in the 500-year period at the beginning of the Latter Age of Degeneration and to spread the five letters of myō, hō, ren, ge, and kyō, which is the substance of all existing things. Furthermore, no one else can form the Most Venerable One (honzon) with the two Buddhas, Śākyamuni and Many Treasures, seated side by side inside the Stupa of Treasures. This is because these (daimoku and honzon) are the gist of the “actual three thousand existences contained in one thought” doctrine expounded in the “Life Span of the Buddha” chapter in the essential section of the Lotus Sūtra, and it should be spread by bodhisattva disciples of the Original Buddha.

Shohō Jisso-shō, Treatise on All Phenomena as Ultimate Reality, Writings of Nichiren Shōnin, Faith and Practice, Volume 4, Page 75

The Pure Lands preached in the pre-Lotus expedient sūtras are mere substitutes tentatively shown by replicas of Śākyamuni Buddha, the Eternal True Buddha. In fact, they all are lands of impurity. Therefore, when the true Pure Land was decided in “The Life Span of the Buddha” chapter of the Lotus Sūtra, the essence of which consists of chapters on the “Expedients” and “The Life Span of the Buddha,” it was declared that this Sahā World is the true Pure Land of the Tranquil Light.

As for the question why, the Lotus Sūtra also recommends the Tuṣita Heaven, the Realm of Peace and Sustenance (Pure Land of the Buddha of Infinite Life), and Pure Lands all over the universe, it is merely that designations of the Pure Lands, such as Tuṣita Heaven and Realm of Peace and Sustenance, preached in the pre-Lotus sūtras are used without modification to name the Pure Lands to be established in this world. It is like names of the three vehicles (śrāvaka, pratyekabuddha, and bodhisattva) mentioned in the Lotus Sūtra, which does not actually preach three different teachings; it preaches the sole teaching leading to Buddhahood. It is stated in the Lotus Sūtra, chapter 23, that those who practice this sūtra “will immediately be reborn in the World of Happiness.” In the Annotations on the Words and Phrases of the Lotus Sūtra, fascicle 10, Grand Master Miao-lê interprets: “This does not mean the Pure Land of the Buddha of Infinite Life preached in the Sūtra of Meditation on the Buddha of Infinite Life.” His interpretation is the same as stated above.

People today without karmic relations with the Lotus Sūtra, wishing to be reborn in the Pure Land to the west, are in fact praying for rebirth in the land of rubble, giving up the Sahā World, which is the true Pure Land. People who do not believe in the Lotus Sūtra will not be able to be reborn even in such lands as Tuṣita Heaven and Realm of Peace and Sustenance, which are in reality the Pure Lands in this Sahā World given such temporary names.

Shugo Kokka-ron, Treatise on Protecting the Nation, Writings of Nichiren Shōnin, Doctrine 1, Pages 68-69

The five characters of Myō, Hō, Ren, Ge, and Kyō are the precious doctrine preached by Śākyamuni Buddha when He entered the Stupa of Treasures sitting by the Buddha of Many Treasures. Buddhas in Manifestation gathered together from all over the universe. The Buddha then invoked bodhisattvas from underground, chose the essence of the Lotus Sūtra and expounded on it for us people in the Latter Age of Degeneration. There should be no doubt about its merit in this world.

Hokke Shuyō Shō, Treatise on the Essence of the Lotus Sūtra, Writings of Nichiren Shōnin, Doctrine 2, Page 215