According to Roy Weldon, among the words conspicuous by their absence in the Book of Mormon is the word "continent." Why would Nephi refer to the new world as an "isle" (2 Nephi 10:20) if the word "continent" would have been in their ancient vocabulary? [Roy E. Weldon, Book of Mormon Deeps, Vol. III, p. 290]
“The Lord Has Made the Sea Our Path and We Are Upon an Isle of the Sea”
Richardson, Richardson and Bentley note that the Book of Mormon claims that some Israelites came to inhabit the land of America (2 Nephi 3:4; 10:20). Isaiah prophesied that Israel would dwell in the isles and coast lands of the north and the west (Isaiah 49:1,3,6,12). Jeremiah saw Israel dwelling in the country beyond the sea, but his words do not appear in the King James Version. The Alexandrian Codex supplies us with the missing text for Jeremiah 23:6: "Judah shall be saved, and Israel shall dwell in the country beyond the sea safely." [Allen H. Richardson, David E. Richardson and Anthony E. Bentley, 1000 Evidences for the Church of Jesus Christ of Latter-day Saints: Part Two-A Voice from the Dust: 500 Evidences in Support of the Book of Mormon, p. 28]
“We Are Upon an Isle of the Sea”
According to a quotation used by Reynolds and Sjodahl, "Sir Isaac Newton observes that to the Hebrews the continents of Asia and Africa were "the earth," because they had access to them by land, while the parts of the earth to which they sailed over the sea were "the isles of the sea." (Commentary on the Book of Mormon, Vol. 1, p. 214)
Thus, Nephi not only refers to the isles of the sea as the location of other remnants of the house of Israel, but he also indicates that he and his people were then living upon an "isle of the sea" when he quite clearly is referring to the great land mass known as the American continent (2 Nephi 10:20-21). The following quotation is of interest:
The Indians almost universally believed the dry land they knew, to be part of a great island, everywhere surrounded by wide waters whose limits were unknown. Many tribes had vague myths of a journey from beyond this sea; many placed beyond it the home of the sun and of light, and the happy hunting grounds of the departed souls. (Quoted from "Library of Aboriginal American Literature," 5:134, in Reynolds and Sjodahl, Commentary on the Book of Mormon, Vol. 1, p. 319) [See the commentary on Helaman 3:8]