Verse 28 begins a set of parallels that will conclude in verse 39. They are a literary set, but we will break them up to make comments on the sets. Verses 28 and 29 set the pattern, although verse 28 is longer than most of the beginning phrases that will come.
Jacob has spoken of the function of the Atonement to satisfy the requirements of condemnation. He has also spoken of our mortal requirement to understand and follow the law. Then he declared that there will be those who, having the law, do not follow it. This brings him to the mortal condition. How is it that one might have the way to God, and reject it to follow the way to the devil?
The answer lies in those who are wise in their own eyes. This reprises Isaiah 50:11 (2 Nephi 8:11): “Behold all ye that kindle fire, that compass yourselves about with sparks, walk in the light of your fire and in the sparks which ye have kindled. This shall ye have of mine hand—ye shall lie down in sorrow.” Isaiah spoke of those who promised light, but produced only sparks. So too does Jacob note the wisdom of the worldly wise will not profit them. Isaiah said they would “lie down in sorrow.” Jacob says that they will perish.
Jacob does add the opposition to this sad state, however. The problem is not wisdom, but the source of wisdom. Those who are truly wise “hearken unto the counsels of God,” or to the law that is given.