The original text here began with yea and. As noted under 2 Nephi 25:5, the text has in a number of cases lost the and from yea and. Also see the discussion under 2 Nephi 9:5 regarding this narrative connector. Here in Jacob 2:6, the critical text will restore the original and. Note that the immediately preceding clause contains an instance of yea and (“which sin appeareth very abominable unto me / yea and abominable unto God”). Perhaps the repetition of the same yea and bothered the 1830 typesetter. In any event, he ended up partially removing the repetition (perhaps unintentionally) by omitting the and from the second yea and. Yet the Book of Mormon has examples of multiple repetition of yea and that have never been changed:
In this verse, there are three occurrences of yea and, two of which are very close to each other, just like originally in Jacob 2:6.
Summary: Restore the and of the connective yea and that originally began Jacob 2:6 (“yea and it grieveth my soul”).