According to the scriptural statement and its interpretations by T’ien-t’ai and Miao-lê, the merit of upholding or protecting even one verse of the Lotus Sūtra is superior to that of giving offerings to all living beings, arhats, or all Buddhas with the seven treasures that spill over all the worlds in the universe. The “Medicine King Bodhisattva” chapter states, “The merit of upholding a stanza or a verse of the Lotus Sūtra is the greatest, to which none can compare.” T’ien-t’ai declares, “A man is light while the Dharma is heavy,” and Miao-lê, “The four stages of birth, rearing, growth and prosperity are different from one another, but they are all based on the Dharma.” Comparing all the living beings in the nine realms against Buddhas (in the realm of Buddhas), the merit of all the living beings is as light as a strand of hair while that of Buddhas is as heavy as a great mountain. Comparing Buddhas against the Lotus Sūtra, on the other hand, the merit of Buddhas is as light as the Brahma King’s robe while one character of the Lotus Sūtra is as heavy as the great earth. When T’ien-t’ai said that a man was light and the Dharma was heavy, he called a Buddha a man and the Lotus Sūtra the Dharma. The sūtras preached before the Lotus Sūtra and commentaries on them all praise the merit of Buddhas. These writings are like Buddhas. The Lotus Sūtra, on the contrary, extols the merit of the sūtra; it is like the parents of the Buddha, the parents who gave birth to those Buddhas.

Hōkyō Hōjū Ji, The Dharma Is More Precious Than Treasures, Wooden Statues or Portraits, Writings of Nichiren Shōnin, Faith and Practice, Volume 4, Page 100

As no Mahāyāna sūtras except one  preach on the basis of the doctrine of “revealing the truth and merging all the provisional,” neither the doctrine of obtaining Buddhahood for the Two Vehicles nor that of attainment of Buddhahood by Śākyamuni Buddha in the eternal past is preached in them. The Lotus Sūtra on the other hand, is expounded on the basis of the “revealing the truth and merging all the provisional” doctrine, thus both doctrines of attaining Buddhahood by the Two Vehicles and the attainment of Buddhahood by Śākyamuni Buddha in the eternal past are revealed in it. Accordingly, it would be the sin of slandering the dharma for followers of those Mahāyāna sūtras to criticize the Lotus Sūtra, but criticism of those Mahāyāna sūtras by believers of the Lotus Sūtra does not constitute slander of the dharma.

Ken Hōbō-shō, A Clarification of Slandering the True Dharma, Writings of Nichiren Shōnin, Doctrine 3, Pages 122-123 

[T]he most important thing for non-Buddhist teachings is, like Confucianism, to prepare the way to Buddhism. This is why some non-Buddhists maintain that the Buddha will be born 1,000 years later, while others insist on 100 years later. It is said, therefore, in the Nirvana Sūtra that what is written in all the non-Buddhist scriptures is nothing but the teaching of the Buddha. Again, it is said in the Lotus Sūtra, chapter eight, “Assurance of Future Buddhahood,” that disciples of the Buddha sometimes pretend to be contaminated with the Three Poisons of greed, anger, and ignorance or show the heretic view denying the law of cause and effect as an expedient means to save the people.

Kaimoku-shō, Open Your Eyes to the Lotus Teaching, Writings of Nichiren Shōnin, Doctrine 2, Page 32

[W]e know that being aware of the past and future precisely is the qualification to be a sage. Without doubt, Śākyamuni Buddha knew that he would pass away in three months in the near future, and he also foretold that the Lotus Sūtra would spread widely in the Latter Age of Degeneration in the far future. Therefore, He could predict things in the far future with His ability of predicting things in the near future or foretell the future state with the knowledge of the present state. This is what the “Expedients” chapter of the Lotus Sūtra expounds, “The truth of all things consists of their appearances, natures … and their consistency from beginning to end.” Who then should be considered as a practicer of the Lotus Sūtra in the last 500-year period? I do not consider myself to be a man of wisdom. However, I can trust my wisdom concerning my predictions of domestic disturbance and foreign invasion. This is not to be bragged about to others. I hope that my disciples understand this. I, Nichiren, am the practicer of the Lotus Sūtra in the Latter Age of Degeneration. Since I follow the footsteps of Bodhisattva Never-Despising, anyone who despises or slanders me, will have his head broken into seven pieces. Whoever believes me, however, will accumulate merit as high as Mount Sumeru.

Shōnin Chi-sanze-ji, The Sage Knows the Three Periods, Writings of Nichiren Shōnin, Biography and Disciples, Volume 5, Pages 20

Just as drops of water fall to become rivers flowing into an ocean and dust particles accumulating to form Mt. Sumeru, the contention of the one person attached to a provisional sūtra will gradually increase, the number of people who do not believe in the true teaching will increase, and even the believers of the true teaching will fall back to believing in the provisional teaching. When believers of the provisional sūtras thus fill the country, the heart of rejoicing at hearing the Lotus Sūtra will be lost and it will be like a country without a king or a human being without spirit. The Lotus-Shingon temples will all fall into disrepair, divine protection by heavenly kings, virtuous gods, dragon god and others will disappear, and sages will all abandon the country. Taking advantage of the situation, devils and demons will take hold of the country, where evil winds will stop staple grains from ripening, and epidemics will spread to lead the people to ruin.

Shō Hokke Daimoku-shō, Treastise on Chanting the Daimoku of the Lotus Sūtra, Writings of Nichiren Shōnin, Faith and Practice, Volume 4, Page 17

The Lotus Sūtra of the fifth period consists of one fascicle of the Sūtra of Infinite Meaning as an introduction, eight fascicles of the Lotus Sūtra, and one fascicle of the Sūtra of Meditation on the Universal Sage Bodhisattva as the conclusion, bringing the total number of fascicles to ten.

The reason for my commentaries on the Four Teachings (Tripiṭaka, Common, Distinct, and Perfect) and the Four Periods (Flower Garland, Agama, Expanded, and Wisdom) is to help others learn what the Lotus Sūtra is. For one cannot correctly understand the teaching of the Lotus Sūtra without learning the pre-Lotus Sūtras, although one may study the pre-Lotus Sūtras without learning about other Sūtras.

In support of this, Grand Master T’ien-t’ai stated in his Profound Meaning of the Lotus Sūtra, “When attempting to spread various sūtras other than the Lotus Sūtra, the essential part of the teaching will not be lost even if a doctrinal analysis of all the teachings of the Buddha is not rendered. When attempting to spread the Lotus Sūtra, however, the essence of the teaching may be lost if a doctrinal analysis is not made.” It is preached in the Lotus Sūtra (chapter 2, “Expedients”), “Although the Buddhas expound various teachings, it is for the purpose of leading the people into the world of the One Buddha Vehicle.” “Various teachings” here refer to all the pre-Lotus Sūtras. “For the purpose of leading the people into the world of the One Buddha Vehicle” means to expound all the scriptures of Buddhism to reveal the Lotus Sūtra.

Ichidai Shōgyō Tai-I, Outline of All the Holy Teachings of the Buddha, Writings of Nichiren Shōnin, Doctrine 3, Page 75

A man should respect these three: his ruler, his teacher, and his parents. Everyone should study these three disciplines: Confucianism, non-Buddhist teachings and Buddhism. …

I-shou was the teacher of Yao, Wu-shih was that of Shun, T’ai-kungwang was of King Wen of Chou, and Lao-tzu was of Confucius. They were called the Four Sages. Even the kings and rulers, who were most respected under heaven, bowed low and all the people respectfully held their hands together in front of them. …

These wise and holy men are sages, but they are as ignorant of the past just as ordinary men cannot see their backs, and they cannot see into the future just as blind men cannot see in front. They merely maintain that if one manages his house well, performs filial devotions, and practices the Five Virtues (benevolence, righteousness, politeness, wisdom and fidelity) in this world, people will revere him, and his fame will spread so widely in the land that a wise king will invite him to be his minister or teacher, or even put him on the throne. Even heaven will come to defend and serve him! …

Ignorant of the past and future, however, these sages cannot help in the future lives of their parents, rulers and teachers. Not knowing what they owe to them in the past, they cannot be considered truly holy and wise. This is why Confucius said, “Truly wise and holy men do not exist in China, but in the land to the west, there is a man called Buddha. He is a true sage.”

Confucius thus indicated Confucianism, which is non-Buddhist (geten), to be the first step toward Buddhism. It would be easier, Confucius knew, for the people to understand the fundamental Buddhist teachings of commandments, meditation, and wisdom if they first learned the fundamental Confucian concepts of rituals and music. He therefore taught the kings’ subjects to be loyal to their rulers, children to be devoted to their parents, and students to respect their teachers. Grand Master Miao-lê therefore declared in his Annotations on the Great Concentration and Insight: “The dissemination of Buddhism in China indeed depended on Confucianism. Buddhism found its way by following on the heels of the rituals and music of Confucianism.”

Kaimoku-shō, Open Your Eyes to the Lotus Teaching, Writings of Nichiren Shōnin, Doctrine 2, Page 29-30

T’ien’tai … makes clear that all things and phenomena in the ten realms are manifestations of the ultimate reality. Since ultimate reality is another name of the Lotus Sūtra, what he states is that all things and phenomena are equal to the Lotus Sūtra. It is a reality of a hell showing hell’s appearance. If its appearance turns into that of the realm of hungry spirits, it is no longer a hell. “All phenomena as ultimate reality” means that Buddhas show Buddhas’ appearance, unenlightened people show their appearance, and the true appearance of all things is the truth of the Lotus Sūtra.

T’ien-t’ai also explains, “The profound doctrine of all phenomena as ultimate reality is the Lotus Sūtra that exists originally and always.” This annotation means that “the deep doctrine of ultimate reality” expounded in the theoretical section of the Lotus Sūtra is called in the essential section the Sūtra of the Lotus Flower of the Wonderful Dharma which exist originally and always. This interpretation is not easy to understand, so please spare no effort in contemplating this.

Shohō Jisso-shō, Treatise on All Phenomena as Ultimate Reality, Writings of Nichiren Shōnin, Faith and Practice, Volume 4, Page 81

It is the Sūtra of Infinite Meaning alone which disparages the sūtras preached during the pre-Lotus period of 40 years or so and lauds just one sūtra, the Lotus Sūtra. It declares that the truth is revealed not in those sūtras expounded in the past 40 years or so, nor in the Sūtra of Infinite Meaning, which is now being preached, or in the Nirvana Sūtra, which is to be preached, but in the Lotus Sūtra alone. Śākyamuni Buddha as well as all Buddhas in the past, present and future appear in the world preaching all the scriptures of Buddhism. They all consider the Lotus Sūtra supreme. Social status, for instance, varies according to the time and circumstance. In the countryside farmers and retainers call warriors “upper class men,” but in the capital region warriors of the Minamoto and Taira clans are men servants while “upper class men” are applied to the members of the three aristocratic families. Again, if masters are called kings, even a farmer is the king of a family whereas the stewards and proprietors of shōen (manor in Medieval Japan) are kings of respective villages, districts, counties and provinces. However, none of these is the great king.

Ken Hōbō-shō, A Clarification of Slandering the True Dharma, Writings of Nichiren Shōnin, Doctrine 3, Pages 120

The Pure Land Sect considers the Buddha of Infinite Life, who is merely a manifestation of Śākyamuni in the Pure Land to the West, to be the lord of this world and abandons Śākyamuni, who is the real lord of this world. The Zen Sect, just like a lowly man with a little virtue despising his parents, despises the Buddha and His sūtras.

They are all confused about the Most Venerable One. It is analogous to the situation before the time of the Three Emperors, when people did not know who their fathers were and behaved like beasts and birds. Those Buddhist schools that do not know of “The Life Span of the Buddha” chapter in the Lotus Sūtra are the same as beasts and birds; they do not know the debt they owe to the Eternal Buddha. Grand Master Miao-lê declared in his Hokke gohyaku monron (500 Inquiries into the Lotus Sūtra): “Eternity in the life of the Buddha, who is our parent, has not been revealed in the pre-Lotus sūtras. (…) If one does not know the eternity in the life of his father, the Buddha, he is also confused about the Buddha land his father governs. Such a man, no matter how capable he may be, is not at all worthy of being a human.”

Kaimoku-shō, Open Your Eyes to the Lotus Teaching, Writings of Nichiren Shōnin, Doctrine 2, Page 75