Mormon names the house of Jacob, a tradition that runs deep into a time before Lehites were in the New World. As part of his invocation of the ancient, Mormon speaks of the blessings that have come through the ancient lineage of Jacob and Joseph, Lehi’s direct ancestors. The specific promise made to the Lehites is the Nephites’ foundational promise, which Mormon restates here. It is quite fitting that he should bring the promise to the conscious present of his narration since, at the time he is writing, he is recording the dramatic demonstration of the promise and the blessings that come from righteousness (the presence of the Messiah), contrasted with the evidence in his own time of the disasters that come from disobedience.