Here in the printer’s manuscript, Oliver Cowdery initially wrote “that they might more easy commit adultery”. Somewhat later, perhaps when he proofed 𝓟 against 𝓞, Oliver supralinearly inserted the definite article the (the level of ink flow is somewhat heavier for the the). In modern English, speakers do not expect the definite article the before “more ”; thus it seems very unlikely that Oliver inserted the the as a result of conscious editing. Most likely, 𝓞 had the the, and Oliver made sure that he copied it into 𝓟. Although there are no other examples of this usage with the in the Book of Mormon text, we can find quite a few examples of “the more ” in the King James Bible:
(Note that in all these examples the adverb ends in -ly, unlike the case of “the more easy” originally here in Helaman 7:5.) There are also four examples of “the more ” in the King James text:
Elsewhere in the Book of Mormon text there are 25 instances of “more ”, and in each case there is no preceding the (this also holds for the many cases of “more ” in the Book of Mormon). The following sampling lists at least one example for each particular adverb:
In only one of these cases (Helaman 4:25) does the original text have a bare adverb, exceeding, which modifies the adjective numerous. In all other cases, the adverb ends in -ly.
Thus the phrase “the more easy” is a difficult reading. The definite article the has been maintained in the text, perhaps because such archaic usage is recognizable as biblical in style. On the other hand, the use of the bare adverb easy is quite unacceptable to modern readers and has therefore been edited in the LDS text to easily, beginning with the 1906 large-print edition and later adopted in the third printing (in 1907) of the 1905 missionary edition and in the 1907 vest-pocket edition. Here in Helaman 7:5, all subsequent LDS editions have maintained the expected adverbial form ending in -ly. Elsewhere, the original text has instances of only easily (six times) as the adverbial form for easy. Nonetheless, the use of the bare adverb sometimes occurs for other adverbs in the original Book of Mormon text. See, for instance, under 2 Nephi 25:20 for cases where the original text had the bare adverb plain instead of the standard plainly. For a complete discussion on the use of the bare adverb in the original text, see under adverbs in volume 3. The critical text will restore the adverbial form easy here in Helaman 7:5 despite its uniqueness in the text.
Summary: Restore the original phrase “the more easy” in Helaman 7:5, the reading of the earliest extant source (the printer’s manuscript); although there are no other examples of “the more ” in the Book of Mormon, such usage is common enough in the King James Bible; the use of the bare adverb easy is also acceptable, especially since similar usage for other adverbs occurs elsewhere in the original Book of Mormon text.