Lehi contrasts his concerns with Laman and Lemuel with his understanding of Nephi's righteousness. Lehi specifically requires that Laman and Lemuel cease their rebellion against Nephi, and uses as his justification for that statement the history of Nephi's spiritual steadfastness and benefits to the family in their journeys.
The contrast in his sons must surely have been painful for Lehi, and the sorrow of his heart for Laman and Lemuel made even more painful when contrasted with the joy he felt in Nephi.