“It Shall Leave Them Neither Root nor Branch”

Joseph F. McConkie, Robert L. Millet
If there were no means whereby the keys of the priesthood could be operative—specially the sealing power (see commentary on verses 5-6)__then the people of the earth, totally unprepared for the Second Advent, would be left without root (ancestry) and branch (posterity); that is, the family order would not have been established on earth.

Doctrinal Commentary on the Book of Mormon, Vol. 4

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