“The People of the First Covenant”
Presumably Mormon is here speaking of the chosen people, the elect, those who have been true to the gospel covenant and me thus entitled to the supernal blessings associated therewith. They are to become joint heirs, coinheritors with Jesus Christ to all that the Father has; that is to say, they receive the blessings reserved for the Firstborn and thus qualify for membership in the Church of the Firstborn (compare 2 Nephi 1:28).
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