This passage is a paraphrase from Isaiah:
This passage is directly quoted in two places in the Book of Mormon (namely, in Mosiah 12:21 and 3 Nephi 20:40), and in both those cases Isaiah 52:7 is quoted without any difference except for the addition of the minor phrase “unto them” twice in 3 Nephi 20:40 (see the discussion there). Joseph Smith left these two direct quotations unchanged in his editing for the 1837 and 1840 editions.
Here in Mosiah 15:14, Joseph Smith made a number of changes in his editing for the 1837 edition. To begin with, he changed each relative pronoun in this paraphrase of Isaiah 52:7 to a consistent who except for the last that (which he changed to an and ). Except for the first relative pronoun (which), all the other relative pronouns in Mosiah 15:14 were originally identical to the that ’s in Isaiah 52:7. After changing the first which to who (since the referent was human), Joseph then apparently decided that the remaining that ’s would be inconsistent with the initial who, so he changed the next two that ’s to who’s. He also replaced the three instances of hath with the plural have since the antecedent for the relative pronouns is they. Finally, Joseph replaced the final that with an and (as already noted), which then led him to change the present tense saith to said. The change of the that to and replaced the final relative clause with a predicate, with this predicate now being conjoined to the preceding relative clause (thus “who have published salvation and said unto Zion”). The said in this last clause should probably be interpreted as the past participle said rather than the simple past-tense said (although the latter is also possible). To make the last predicate clearer, Joseph could have added have before said (“who have published salvation and have said unto Zion”), but this emendation would have seemed a little awkward.
One additional problem for this paraphrase in Mosiah 15:14 is the punctuation between the last two relative clauses of the original text. The 1830 compositor set a semicolon between these two clauses but only commas between the preceding pairs of relative clauses. This inconsistency in punctuation was further exacerbated when the 1837 change of that to and was implemented since readers normally expect a full clause rather than a conjoined predicate after a semicolon.
The critical text will, of course, restore the original paraphrase here, including its mixture of an initial which (meaning ‘who’ in modern English) followed by three that ’s. It will also restore the cases of hath that Joseph Smith edited to have as well as the original saith. For further discussion, see under infl al endings and which in volume 3.
Summary: Restore the original relative pronouns and present-tense verb forms in Mosiah 15:14; for consistency in punctuation, the semicolon before the last relative clause should be replaced with a comma in the standard printed text.