Although the scattered tribes of Israel are lost to the knowledge of man, they are not lost to God. He knows where they are, “for he knoweth whither he hath taken them” (3 Nephi 17:4). His knowledge of them and the Savior’s visit to the lost tribes of Israel suggests the possibility that we will someday have access to other accounts of Jesus’s visits to His sheep.
Elder Neal A. Maxwell observed: “Lost books are among the treasures yet to come forth. Over twenty of these are mentioned in the existing scriptures. Perhaps most startling and voluminous will be the records of the lost tribes of Israel (see 2 Nephi 29:13). We would not even know of the impending third witness for Christ except through the precious Book of Mormon, the second witness for Christ! This third set of sacred records will thus complete a triad of truth. Then, just as the Perfect Shepherd has said, ‘My word also shall be gathered in one’ (verse 14). There will be ‘one fold and one shepherd’ (1 Nephi 22:25) in a welding together of all the Christian dispensations of human history (see D&C 128:18)” (in Conference Report, Oct. 1986, 70; or Ensign, Nov. 1986, 52).