Lehi highlights the necessity of preaching this good news to all of earth’s inhabitants. These principles affect all humankind, whether they know them or not. But their conscious awareness of the truth will speed their acceptance of the Messiah’s atonement. In addition to redeeming humankind from sin, the Atoning Messiah also effects redemption from death.
The succinctness of this explanation implies that Lehi is reiterating information that his listeners already know. It is an orientation to the general direction of his discourse—a reminder of familiar concepts.