Rhetoric: Nephi now becomes personal. Since his listeners “know these things,” that knowledge condemns them since they do not act on it. They continue to accept these prophets, even though they are obviously drifting into apostasy. They can resolve the paradox only by accepting these prophets’ Messianic testimony.
When Nephi accuses his listeners of “reject[ing] all these things,” he is not referring to the prophets. Clearly they still accept the prophets. He is referring to prophecies of the coming Messiah.