With no opposition, or opposites, the creation of physical bodies for Heavenly Father’s children would have been meaningless and purposeless, “a thing of naught.” God’s eternal plan would be annulled, along with his wisdom, power, mercy, and justice.
Lehi laid out his argument like a master philosopher. The pure logic is the following: no law, no sin; no sin, no righteousness; no righteousness, no happiness; no righteousness nor happiness, no punishment nor misery; and if all these principles do not exist, then God does not exist either—nor do we, nor the earth. But Lehi testified that God does exist, as evidenced by all his creations.