Jephthah shews that the Israelites did not take the land of
   the Moabites or Ammonites, but that of the Amorites, which
   they had conquered from Sihon their king; and although the
   Amorites had taken the lands in question from the Ammonites,
   yet the title by which Israel held them was good, because they
   took them, not from the Ammonites, but from the Amorites.

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