1 Nephi 2:19

19 And it came to pass that the Lord spake unto me, saying: Blessed art thou, Nephi, because of thy faith, for thou hast sought me diligently, with lowliness of heart.

Interestingly, these same words are recorded in Helaman 10:4. “Blessed art thou, Nephi…” When we make a covenant with the Lord, we are expected to endure to the end, but that doesn’t stop Him from rewarding us now for the faithfulness and diligence we demonstrate. It seems like when the Lord blesses these people in the scriptures in this manner, He gives them the reason. Nephi 1, in this verse, is blessed because of his faith, as evidenced by the fact that he had sought the Lord diligently, with lowliness of heart. The other Nephi (in the book of Helaman) was blessed “for those things which thou hast done.” Then the Lord tells what those things were: teaching the gospel. The same thing happens at the beginning of this chapter with Lehi (1Nephi 2:1). The same thing happens again with Enos (Enos 1:5–8). The index puts it in perspective a bit. It lists scriptures relating to reasons why people would be blessed. “Blessed are they who seek to bring forth Zion” (1 Nephi 13:37), “who have labored in the vineyard” (Jacob 6:3), “they who humble themselves” (Alma 32:13–16), “endure to the end” (Alma 38:2), “come unto Christ” (3 Nephi 9:14). And on it goes. The blessings we receive are related to the commandments we keep (D&C 130:20–21)