Laman and Lemuel's self justification continues with their denial of the original premise of their father's vision. In order to create their own rationale for their opinions, they are required to deny not only Nephi, but their father, and must deny for both of those men any true inspiration. From a cultural standpoint (certainly not a spiritual one) Laman and Lemuel would be unable to deny a command from God. They must therefore deny that the command came from God, and deny the messengers.