There are actually two ways of looking at the phrase “thus have I heard.” The difference is which way or which direction “thus have I heard” points. In one understanding, “thus have I heard” points to the text that follows. So in this interpretation Ananda is saying what he heard from the Buddha and it is titled Myoho Renge Kyo. The other interpretation is “thus have I heard” is pointing to Myoho Renge Kyo, and what follows is an explanation, or interpretation of Myoho Renge Kyo. In the first understanding the text of the sutra is primary, in the second the text is secondary to the title. As different sentence constructions it might look like this. ‘Myoho Renge Kyo is what I heard’ versus ‘This is what I heard. The Buddha one …’ The difference is slight but important. In the first Myoho Renge Kyo is the most important thing and all that follows is a way to understand Myoho Renge Kyo. The second understanding places the text of the sutra as key and the title is a summary of the contents.
Nichiren argues that “thus have I heard” is referring to Myoho Renge Kyo and this supports the conclusion that chanting the title as a single practice is very much appropriate and correct. Everything then recounted in the text of the sutra is similar to an exegesis of the most important thing, which is Myoho Renge Kyo.
Lecture on the Lotus Sutra