Lehi extends his doctrinal treatise on agency, the Fall, and the Atonement to his son Jacob and to all his sons (vv. 28–30). His having “chosen the good part,” suggests he has selected the most important and appropriate teachings, not saying everything that could be said about these subjects. The Prophet from whom he selected these words was Moses whose five books were “engraven on the plates of brass” (1 Nephi 5:10–11). His object was to make the welfare of children’s souls the object of every righteous parent.