The substitution of the Levitical Priesthood for the firstborn Israelites was established in Numbers chapter 3. This 'authorized' Torah also removed the Korahites from the Temple of Solomon, adding the Revolt of Korah to the Torah, set long before the Israelites entered Canaan. The Sons of Korah, or Korahites, were a rival priesthood to the Levites that administered the Temple of Solomon from the time of Solomon until Josiah. They are believed to have originally been the priesthood of El Elyon at the Jebusite Temple before David conquered them. Solomon, David's youngest son, was an unlikely heir, and not the original heir apparent, as his elder brother Adonijah attempted to succeed David by marrying Abishag the Shunamite, David's youngest wife, who was twelve years old at the time. However, Solomon's Jebusite mother Bathsheba, and the prophet Nathan conspired to place the fifteen-year-old Solomon on the throne and then purged the government of non-Jebusites, who appear to have all supported Adonijah. The Sons of Korah were the authors of some of the Psalms, and are documented as existing in Judea as late as the Persian era, although seem to have disappeared by the early Greek era. Some have theorized they may have formed the priesthood of the Essenes (Nazarenes) in the late-Persian era, as the Essenes had another Torah, and used different holy books from the other Jews, such as the books of Enoch and Jubilees.