In the manuscripts, Oliver Cowdery frequently mixed up the spelling of bear and bare. In most cases, we are able to readily determine whether the context requires the present-tense bear or the past-tense bare. But in some cases, either reading will work, at least in theory. In this passage, 𝓞 apparently read bear since both 𝓟 and the 1830 read bear. In the editing for the 1920 LDS edition, bear was emended to bare. The same change was made in the following chapter:
The nearest other occurrences of bearing witness in this part of 3 Nephi almost always refer to the disciples and the multitude as doing so in the past tense; but in one case there is clear evidence that bearing witness can be expressed in the present tense (marked below with an arrow):
We see from these examples that both “did bear record” and “do bear record” occur. One interesting relationship is that the past-tense “did bear” occurs when the syntactically closest clause is in the past tense:
But in the one case of “do bear”, the syntactically closest clause is the subsequent sentence, which is directly linked to the preceding present-tense clause:
This correlation in tense between closely associated clauses argues that in 3 Nephi 17:21 and 3 Nephi 18:37 the verb should be in the past tense (in agreement with the 1920 editing):
There are two cases in 3 Nephi 19 where a present-tense “do bear” occurs in an otherwise past-tense context, but in both these cases there is a preceding reference in the past tense to what was observed by the same witnesses, with the result that the reference to bearing record can be in the present tense:
For both these cases, the present-tense auxiliary verb do is firm, while here in 3 Nephi 17:21 and 3 Nephi 18:37 we have the difficulty of deciding between the homophones bear and bare. But also note that there are two instances in 3 Nephi 17 where the text first uses the past tense to refer to the multitude bearing record and then follows this with a comment in the present tense regarding the continuing nature of their witness:
Thus the critical text will accept the 1920 emendation of bear to bare in 3 Nephi 17:21 and 3 Nephi 18:37. For further discussion of the two cases in 3 Nephi 19 of “do bear”, see under 3 Nephi 19:14; also see the general discussion under bear in volume 3.
Summary: Accept the 1920 LDS emendation of bear to bare in 3 Nephi 17:21 and 3 Nephi 18:37 since the syntactically closest clauses for these two passages occur in the past tense.