I’ve previously discussed Isaiah 18:1, which relates a prophecy about the location of the latter-day Zion, which, from the perspective of Isaiah living in Israel, is beyond the rivers (waters) of Ethiopia. I think that’s how Nephi knew he had to sail around Africa to reach the promised land.
Zephaniah, another Old Testament prophet, who was a contemporary of Lehi.
“Zephaniah saw our day and beyond. In it he both suffered and rejoiced. He suffered in spirit because of the desolation and destruction which he saw, but he was able to use this as a warning and threat to his own people. In the redemption and final blessings of Israel he saw a ray of hope to extend to Judah. No prophet has written more clearly or vigorously of the Day of the Lord. Zephaniah must be added to the list of prophets who give us a grave warning of disaster.” (Sidney B. Sperry, The Voice of Israel’s Prophets, p. 388.)
It’s significant that like Isaiah, Zephaniah referred to the land “beyond the rivers of Ethiopia” as the place from which “my suppliants” [those who seek the Lord] ” even the daughter [descendants] of my dispersed [Lehi was dispersed] shall bring my offering [as one commentator put it, “themselves as an offering to the Lord, souls and bodies, with all other spiritual sacrifices of prayer, praise, and well doing”].
Here is the verse in context:
I won’t take the time to go through this in more detail now, but it’s something to consider, together with Isaiah 18. The prophets knew where the promised land would be, and where the gathering would begin when the gospel was restored in the last days.
Source: Book of Mormon Concensus