“Their seed” refers to the descendants of the mingled Nephites and Lamanites; but his address “to the Gentiles who have care for the house of Israel” is rather mysterious. It describes a relationship between Israel and the Gentiles that has no obvious antecedent and which he does not explain. Therefore, he assumes that his readers already understand it. In fact, he is alluding to passages from Isaiah quoted three times earlier but only in the holographic text of Nephi1. (See 1 Nephi 21:22–23 and 2 Nephi 6:6–7, one verse of which Jacob repeats in 2 Nephi 10:9.) The quotation is:
Thus saith the Lord God, Behold, I will lift up mine hand to the Gentiles, and set up my standard to the people: and they shall bring thy sons in their arms, and thy daughters shall be carried upon their shoulders.
And kings shall be thy nursing fathers, and their queens thy nursing mothers: they shall bow down to thee with their face toward the earth, and lick up the dust of thy feet; and thou shalt know that I am the Lord: for they shall not be ashamed that wait for me. (Isa. 49:22–23)
These are the only verses in our current Book of Mormon that clearly position the Gentiles as Israel’s protectors. The Messiah’s discourse at the temple explains the Gentiles’ role in bringing the gospel and the Book of Mormon to Lehi’s descendants, but he never described them as protectors.