On 1 November 1831, Joseph Smith, Jr. received a revelation:

“And also the Lord shall have power over his saints, and shall reign in their midst, and shall come down in judgment upon Idumea, or the world.”

   Doctrine and Covenants (Hiram, OH: The Church of Jesus Christ of Latter-day Saints, 1 November 1831), Section 1:36.

In proclaiming Idumea as “the world,” young Joseph must not have known that this Biblical word is Hebrew for Edom or Esau.  These Edomites were cave dwellers near Moab.  They were totally annihilated after the invasion of the kingdom of Judah.