The printer’s manuscript reads “in as much as”, but the 1830 edition has “insomuch as”. The use of insomuch appears to be an error. As discussed under 2 Nephi 1:20, the text otherwise systematically uses inasmuch when referring to keeping the commandments of God (19 times); there are no other instances where insomuch is used in this context. Moreover, there is evidence in the transmission of the text for accidentally replacing inasmuch with insomuch:
But there are no examples in the text of change in the other direction, from insomuch to inasmuch. To be sure, there is not a lot of evidence from transmission errors involving inasmuch and insomuch. For a third case where an original inasmuch may have been replaced by insomuch, see under 2 Nephi 9:15. As explained under that passage, various syntactic and semantic generalizations favor inasmuch over insomuch in contexts like the one here in 3 Nephi 5:22. Therefore, the critical text will here accept inasmuch, the reading in 𝓟, as more probable than insomuch, the 1830 reading.
Summary: Restore in 3 Nephi 5:22 the reading of the printer’s manuscript, “inasmuch as the children of Lehi hath kept his commandments / he hath blessed them”; the reading with inasmuch rather than the 1830 reading with insomuch is supported by usage elsewhere in the text as well as by the tendency to replace inasmuch with insomuch in the history of the text.