In Nephi’s context, this declaration is relevant to warning his brothers (and us) that God called Nephi, and is with him. It was God whose providential hand has been present throughout Nephi’s actions. He was with him in returning to retrieve the brass plates. He helped Nephi overcome Laban. God has been with Nephi in receiving revelation, in leading the return to get Ishmael’s family to join with them, and in giving the prophetic testimony of Christ. God has revealed to Nephi the warning of future events in the lives of his and all future generations. God chose Nephi and has both “brought him” and will “make his way prosperous.”
In this context, the “prosperous” nature of Nephi’s life does not mean wealth. It means his life will be filled with God’s favor. Knowledge of the mysteries is the real prosperity Nephi enjoyed, which came through great difficulties and challenges. We would do well to seek such “prosperity” for ourselves. Having God’s favor and experiencing “prosperity” from God does not mean worldly success. Those who experienced the greatest prosperity from God, suffer terribly in mortality. Hardly a great prophet in any dispensation has been given much worldly success. Comfort and peace eludes the most chosen of His children because they gain deep understanding through their personal tribulations. It is obtained in no other way. Joseph’s wisest written reflections were made while in a Missouri dungeon. We learn (and that is what we should value most) through the things we suffer. In that respect we are all like Christ.