Back to Jacob 2. Even if I concede that verse 30 is a loophole for the abomination of plural marriage, people desiring to take this concept on (mostly men) need to take extreme care. The historical LDS narrative of "GOD can command whatever He wants, including polygamy" is true with a massive caveat. When GOD tells you personally, you can then choose to break a commandment. If He is not telling you to your face that you can violate one of the 10 Commandments, then you must take stock of your motives. Is it a desire to obey or a desire to get away with something?
Here is my example using another serious sin, the taking of life. Two books earlier in the Book of Mormon, the LORD (via the Spirit) "constrains" Nephi to kill Laban. Many people have a problem with this, but I do not. Laban deserved to die for violating the provision for armed robbery in the Law of Moses, and the brass plates were worth killing for. But that does not justify anyone other than Nephi in taking a life. If I were foolish enough to use the Mormon's church rationale here of "if it is in the scriptures once or twice then GOD permits it," I can just start randomly killing people. Sounds patently ignorant, and it is. It is just as stupid as using one verse in all of the Book of Mormon to create a culture of adultery that has seriously crippled the restoration of the Gospel of Jesus Christ.