Moroni knows that he is acting under the spirit of divine prophecy, for God has declared through the voice of His chosen prophets across time that His word—in this case concerning the remnant of Joseph—will come forth in the latter days to confirm His everlasting gospel. It is therefore expedient that we receive His word in the spirit of thanksgiving and obedience and act upon it in all diligence in order to secure a place for ourselves and our loved ones in the eternal mansions on high. Let us come unto Christ, lay hold on the gifts of God, and shun evil.