The Book of Mormon frequently switches between plural and singular when referring to what has been written. A good example of this shifting in number is found in a passage that uses the singular pronoun it to refer to “these records”:
Here in 2 Nephi 33:4, the text originally read “the things which I have written”, which was then followed three times by the singular pronoun it in collectively referring to what had been written (“it persuadeth them … it maketh known unto them … it speaketh of Jesus”). In his editing for the 1837 edition, Joseph Smith attempted to correct this grammatical difficulty by changing things to the singular word in the printer’s manuscript. But the 1837 compositor ended up setting words rather than word, thus maintaining the original shift in number in the standard text. As discussed under 1 Nephi 5:21, the critical text will retain such shifts in number whenever the text refers to written records, including this one involving the word things.
Using the plural things to refer to subject matter is characteristic of the Book of Mormon text. There are, for instance, 108 instances where the original text refers to the writing of things. But there are also two instances where the text refers to the writing of a singular thing:
Of course, the text can also refer to the writing of words (40 times in the original text). And there is also one instance where the text refers to the writing of the word of God:
In general, either things or words can be written. And sometimes the text refers to a particular thing or the word of God as being written. The statistics show that in most instances either the plural things or words is expected. In each case we therefore follow the earliest textual sources in determining whether the correct reading is things or words—or whether either of these occur in the singular rather than the expected plural.
Summary: Restore the original plural things in 2 Nephi 33:4, the reading of the earliest text for that passage; the Book of Mormon text sometimes uses the singular pronoun it to collectively refer to the things that have been written in records.