Joseph Smith, in his editing for the 1837 edition, deleted the to it after did go. There is no referent for the pronoun it, so perhaps Joseph considered this reading anomalous.
One possibility is that the original phrase actually read “the servants did go to and labor with their mights”. This colloquial phrase, “go to and ”, is very prominent in the olive tree allegory:
There is also one other occurrence of the phrase “go to and ” in the Book of Mormon text:
Perhaps here in Jacob 5:72, Oliver Cowdery accidentally added the object pronoun it during the early transmission of the text. Consider, for instance, the following example where he made such an error, at least momentarily, when he copied from 𝓞 into 𝓟:
In his supralinear correction for this passage, Oliver initially wrote read it, but then he erased the it (see 1 Nephi 1:11 for discussion of this error). This initial error shows that Oliver could have accidentally added an it also in Jacob 5:72. In other words, perhaps Joseph Smith should have deleted only the pronoun it when he edited the text for Jacob 5:72. In fact, it is even possible that he intended to do that but accidentally ended up deleting the preceding to as well.
The Oxford English Dictionary gives examples of this expression “go to” (see definition 93 under go), including an example from the 1400s (in Palladius on husbondrie) that is quite close to the themes of the olive tree allegory: “go to And transplaunte hit” (that is, “go to and transplant it”). The OED gives the meaning for “go to” as ‘to go about one’s work, to get to work’, noting also that it is chiefly found in the imperative as an exhortation.
The four established examples of “go to and ” in the olive tree allegory involve major, long-term activities. The examples in Jacob 5:62 and Jacob 5:71 refer to the general activity of laboring, and the one in Jacob 5:61 refers to the calling of other servants to help with this general labor. And the first example (in Jacob 5:49) refers to the major work of hewing down trees and burning them. These semantic regularities suggest that the example in Jacob 5:72 should have actually read “go to and labor”. Yet the proposed reading “go to and labor” here in verse 72 would be in the past tense and would be the only one for which “go to” does not function as an exhortation. However, the use of the periphrastic did allows the infinitive forms go and labor to be conjoined; thus the phrase “did go to and labor” in Jacob 5:72 is possible, but “went to and labored” seems problematic.
There are also two other imperative examples in the current Book of Mormon text of “go to” with the same meaning but without any following conjoined predicate:
This last example is particularly interesting in that the text there originally read “go to it”, just as Jacob 5:72 originally did. But unlike his editing for Jacob 5:72, in Enos 1:8 Joseph Smith deleted only the it. This example could therefore be used to support the idea that Joseph should have deleted only the it in Jacob 5:72. But the editing here is not as important as the realization that the original text for Enos 1:8 provides direct support for the original reading in Jacob 5:72 (namely, “the servants did go to it and labor with their mights”).
The King James Bible has 11 examples of the colloquial “go to”, all without a following and:
Although the Bible has no examples of “go to it”, there are other biblical examples of idiomatic verbs having “to it”, where it has no specific referent:
The fact that the King James Bible has all these examples of to it in italics shows that this phrase represents idiomatic English not expressed in the original languages, Greek and Hebrew. Thus there is indirect biblical support for the original expression “go to it” in Jacob 5:72 and Enos 1:8.
Joseph Smith’s edited text in Jacob 5:72 (from “the servants did go to it and labor” to simply “the servants did go and labor”) is, of course, also a possible reading for the original text. Of the 14 examples of “go and ” in the original Book of Mormon text, one is found in the olive tree allegory:
One might argue that this passage also represents an error for “go to and ”. However, the Lord’s command here involves going and doing a specific task. The labor is not a general and long-term activity, but instead it describes a well-defined task (namely, “pluck the branches from a wild olive tree”). And when we look at the 13 other original examples of “go and ”, the text assumes that a specific well-defined task is intended:
Thus the example of “go and pluck” in Jacob 5:7 is probably not an error for “go to and pluck” and should not be changed. And since Jacob 5:72 definitely involves a continuing task (“the servants did go to it and labor”, the emendation to “the servants did go and labor” is inconsistent with all other instances in the Book of Mormon text of the expression “go and ”.
Summary: Accept the original use of the expression “go to it” in Jacob 5:72 and Enos 1:8; Joseph Smith’s emendation of Jacob 5:72 to “the servants did go and labor” is inconsistent with the 14 cases of “go and ” in the Book of Mormon text.