Here is one case where the relative pronoun which was edited to who despite the fact that standard English actually prefers which in this kind of construction. Consider, for instance, the following statistics for present-day English from the Internet site m> on 7 November 2002:
which of us | 26,800 |
which one of us | 18,500 |
who of us | 8,570 |
which of you | 35,600 |
which one of you | 25,600 |
who of you | 6,510 |
which of them | 81,400 |
which one of them | 21,200 |
who of them | 1,620 |
Note in each case that the expression “which of X” is more frequent than the corresponding “which one of X”, while the expression “who of X” is relatively infrequent.
Joseph Smith’s editing of which to who in this expression is found only here. Elsewhere he kept the original which’s:
Both these passages are found in quotations from the King James Bible. We should also note that both are wh-questions, so there are distinct differences between these two examples and the relative clause example in 1 Nephi 3:11. The King James text always uses which rather than who in the expression “which of X” (19 times, including the two passages that the Book of Mormon quotes from, Isaiah 50:1 and Matthew 6:27).
In any event, Joseph Smith’s editing here in 1 Nephi 3:11 is unusual and unnecessary. He was probably motivated (especially here in the beginning of his editing for the 1837 edition) to change every which that referred to humans to who. See which in volume 3 for a complete discussion of the change to who.
Summary: The construction “which of X” is preferred in standard English, so the 1837 editing to “who of X” in 1 Nephi 3:11 is unusual; the critical text will restore the original “which of us” in 1 Nephi 3:11.