Day 3 covers the first half of Chapter 2, Expedients.

Last month I opened the Buddha’s explanation of the need for expedients. This month I continue with the Buddha’s description of the insight of the Buddhas.

Sariputra! The insight of the Tathagatas is wide and deep. [The Tathagatas] have all the [states of mind towards] innumerable [living beings,] unhindered [eloquence,] powers, fearlessness, dhyana-concentrations, emancipations, and samadhis. They entered deep into boundlessness, and attained the Dharma which you have never heard before.

Sariputra! The Tathagatas divide [the Dharma] into various teachings, and expound those teachings to all living beings so skillfully and with such gentle voices that living beings are delighted. Sariputra! In short, the Buddhas attained the innumerable teachings which you have never heard before. No more, Sariputra, will I say because the Dharma attained by the Buddhas is the highest Truth, rare [to hear] and difficult to understand. Only the Buddhas attained [the highest Truth, that is,] the reality of all things’ in regard to their appearances as such, their natures as such, their entities as such, their powers as such, their activities as such, their primary causes as such, their environmental causes as such, their effects as such, their rewards and retributions as such, and their equality as such [despite these differences].

This true nature of reality is discussed in Lotus Seeds:

Though the One Vehicle is expressed throughout the first half of the Lotus Sutra, the core passage, according to Nichiren Shonin, is in the very first prose passage of the second chapter, “Tactfulness.” In that passage, the Buddha first reveals to his wisest disciple, Śāriputra, that the teaching of the Buddha is beyond the ability of even his most advanced disciples to understand. He tells Śāriputra that the true nature of reality can only be understood by the buddhas, and that this true nature of reality consists of Ten Factors (or “suchnesses”). … These Ten Factors are integral parts of the law of cause and effect, and they are found in the lives of all beings. They are present in the lives of ordinary beings, and they are present in the lives of Buddhas. It is due to the common ground of the Ten Factors that ordinary people are capable of becoming buddhas, and buddhas are capable of appearing as ordinary people.
Lotus Seeds