1 Nephi 22:16 - 22:20
1 Nephi 22:16 For the time soon cometh that the fulness of the wrath of God shall be poured out upon all the children of men; for he will not suffer that the wicked shall destroy the righteous.
It will not be long before the Lord allows people to destroy themselves so that the righteous may be able to live in peace and happiness.
1 Nephi 22:17 Wherefore, he will preserve the righteous by his power, even if it so be that the fulness of his wrath must come, and the righteous be preserved, even unto the destruction of their enemies by fire. Wherefore, the righteous need not fear; for thus saith the prophet, they shall be saved, even if it so be as by fire.
And it will be by the Lord's direct influence that the righteous are preserved; not be accident or by an oversight by the wicked. The wicked by be destroyed by the Lord as he told us in 3 Nephi. Because the Lord will do this, the righteous need not be concerned about their safety. He will show the righteous what to do to in order to avoid this destruction.
1 Nephi 22:18 Behold, my brethren, I say unto you, that these things must shortly come; yea, even blood, and fire, and vapor of smoke must come; and it must needs be upon the face of this earth; and it cometh unto men according to the flesh if it so be that they will harden their hearts against the Holy One of Israel.
This destruction will happen soon. (How long “soon” is has always been a subject of speculation and/or concern). It will happen by fire and blood and vapor of smoke. I assume that this refers to the events of 3 Nephi 8 and also the events leading up to it in the book of Helaman and 3 Nephi.
The blood I assume is by warfare between the wicked and the fire and smoke the destruction by natural forces of nature. This events would not happen if folks would obey the gospel and live by its precepts.
1 Nephi 22:19 For behold, the righteous shall not perish; for the time surely must come that all they who fight against Zion shall be cut off.
Those to do live by its precepts will survive the destructions but those who have rebelled against it will fall victim to the Lord’s wrath.
1 Nephi 22:20 And the Lord will surely prepare a way for his people, unto the fulfilling of the words of Moses, which he spake, saying: A prophet shall the Lord your God raise up unto you, like unto me; him shall ye hear in all things whatsoever he shall say unto you. And it shall come to pass that all those who will not hear that prophet shall be cut off from among the people.
This preservation will occurred because the people have listen to and obeyed a very special prophet. He will be like Moses in that those who will follow His directions will be lead out of the wickedness of the world and be preserved from evil forces. While those who will not will fall victim to their own ways and will be separated from the righteous.