In this passage, the first verse has the present-tense knoweth, which sounds strange given the preceding use of the future modal will (“they will be among the Gentiles”). In addition, the subject is plural and knoweth is supposed to have a third-person singular subject in standard biblical English. Accordingly, the editors for the 1920 LDS edition emended knoweth to shall know, as suggested by the language in the following parallel verse: “and the Jews shall know them not” (not “and the Jews knoweth them not”). This editing therefore eliminated an unusual presenttense verb form and increased the parallelism:
verse 27 (1920 revision) verse 28
and behold
they will be among they will also be among
the Gentiles the Jews
and the Gentiles and the Jews
shall know them not shall know them not
The 1920 change was intentional since it is marked in the committee copy.
The phraseology here in 3 Nephi 28:27–28 may be related to John the Baptist’s language in John 1:26, which is quoted (along with other biblical sentences) in 1 Nephi 10:8:
But these statements do not refer to the future, as 3 Nephi 28:27–28 does.
The original manuscript undoubtedly read knoweth in verse 27 since both the 1830 edition and the printer’s manuscript agree here. It is doubtful that Oliver Cowdery, the presumed scribe here in 𝓞, would have accidentally replaced a dictated shall know with knoweth (or that Joseph Smith would have made this particular change as he dictated the text). The emended reading shall know definitely works better, but it very likely does not represent the original text. Obviously, the use of knoweth gives an immediacy to the narrative, but then one wonders why the same present-tense construction wasn’t used in verse 28. In any event, the critical text will restore the original use of knoweth in verse 27, despite its difficulty.
Summary: Restore in 3 Nephi 28:27 the original use of knoweth (“the Gentiles knoweth them not”), the reading of the earliest textual sources (𝓟 and the 1830 edition).