“In that day” refers to the time when the “plain and precious parts” will be restored. The Messiah is here identified as the Lamb of God, a designation of great power to Nephi who understood what a sacrificed lamb represented in Mosaic law. (See commentary accompanying 1 Nephi 10:9–11.) The time of restoration is also the time when the Messiah would manifest himself “in power, in very deed.” While the Savior’s personal manifestation in power has yet to occur, the restoration of the gospel and Joseph Smith’s first vision are direct fulfillments of other parts of this prophecy.