These verses juxtapose time frames and references. Verse 21 alludes to Moses, who led Israel through the desert and brought water from the rock. Verse 20 calls Israel forth from Babylon rather than the historically accurate Egypt, thus connecting the first exodus from captivity to the second exodus from Babylonian captivity. While Israel is captive in Babylon, Yahweh will lead them, just as he led them in Egypt.
The lament of verse 22 recognizes that, despite Yahweh’s power and the prophets’ call, they experience no peace. Linking this lament to verse 18’s accusation provides the proper context. Everything might have been different. The possibility was there, Yahweh was there, and Yahweh performed miracles for them. Yet there is no peace because Israel has chosen not to follow Yahweh. The Lehites have also brought about their own sufferings because of their unbelief, even though they have seen miracles and clearly heard prophets.
Variant/Translation: Verse 22 extends the beginning of the phrase. King James Version ends with: “There is no peace, saith the Lord, unto the wicked.” Again, the change is to an italicized phrase, but Joseph Smith did not eliminate it. Rather he added a smoother transition from the previous passage to “no peace.” The Book of Mormon introductory phrase integrates the text better than the simpler KJV declarative.
Text: There is no chapter break at this point in the 1830 edition, but a chapter break was created here in 1879 by Orson Pratt to match the chapter arrangement of Isaiah in the King James Version (and other modern texts of the Bible). If Joseph Smith had merely been copying from the King James Version, then he would probably have followed its chapter divisions; but Nephi did not have this arrangement on the brass plates.