Isaiah announces his text as a revelation. The introduction of Isaiah, son of Amoz, as the one who saw the vision clearly marks this as the beginning of a new text for Isaiah, not one that might continue in theme or subject from a previous text. In the 1830 edition of the Book of Mormon, this is the beginning of a single chapter that comprises what we currently have as chapters 12-15. The modern chapter divisions were created to match with the chapter and verse divisions of Isaiah in the standard versification.
It should also be noted that while this introduction begins the citation of Isaiah, and marks the beginning of Isaiah’s text, it does not mark the beginning of Nephi’s text. Our current chapter 11 is Nephi’s introduction to Isaiah, and is not separated from the beginning of Isaiah’s prophecy in the 1830 edition. Thus the 1830 edition has a single chapter which is represented by chapters 11-15 in the current text.
Textual analysis: The text of Isaiah 2:1-4 is nearly identical to that found in Micah 4:1-4
Micah 4:1 But in the last days it shall come to pass, that the mountain of the house of the LORD shall be established in the top of the mountains, and it shall be exalted above the hills; and people shall flow unto it.
Micah 4:2 And many nations shall come, and say, Come, and let us go up to the mountain of the LORD, and to the house of the God of Jacob; and he will teach us of his ways, and we will walk in his paths: for the law shall go forth of Zion, and the word of the LORD from Jerusalem.
Micah 4:3 And he shall judge among many people, and rebuke strong nations afar off; and they shall beat their swords into plowshares, and their spears into pruninghooks: nation shall not lift up a sword against nation, neither shall they learn war any more.
Micah 4:4 But they shall sit every man under his vine and under his fig tree; and none shall make them afraid: for the mouth of the LORD of hosts hath spoken it.
Both Micah and Isaiah are thought to be written in the same basic time frame, and it is possible that one saw the writings of the other, or both are citing a prophecy known to both, the source of which is not available today. “Scholars differ in their opinions on which of these possibilities best explains the textual similarities.” (Ludlow, Victor. Isaiah: Prophet, Seer, and Poet. Deseret Book, 1982, p. 86.)