Well, let's see: The Utah Mormons said in 1830 (in Book of Mormon)...
...that polygamy was an "abomination"
...Then, the following year, when Joseph Smith's schemes started in on bedding a 16 yo housekeeper...polygamy secretly "evolved" to being an "in" thing...
...Then, Smith began greatly accruing multiple wives in the early 1840s...
...and getting some of his fellow leaders to do the same...
...and then polygamy "evolved" within Mormondom so that between the 1850s and 1880s, Lds leaders were expected to have multiple wives -- touting that it was a condition of the highest degree of afterlife glory...
...and then the "brakes" began to be applied to Mormon polygamy in 1890 -- de-evolving...
...and by the early 1900s, few such unions were being secretly solemnized by Lds leaders anymore...
By 1945, the last MAINSTREAM Lds polygamous "prophet" had passed on...
And polygamy for the mainstream Mormons had been fully relegated to (a) the afterlife; and (b) When the Mormon Jesus returns.
And so...just because groups like the mainstream and non-mainstream Mormons have attacked in ALL THREE last centuries (21st, 20th, 19th) the institution of monogamy, that we have to let the marriage evolutionists dictate to everybody else what marriage is?
THE BOOK OF JACOB
THE BROTHER OF NEPHICHAPTER 224 Behold, David and Solomon truly had many wives and concubines, which thing was abominable before me, saith the Lord.
25 Wherefore, thus saith the Lord, I have led this people forth out of the land of Jerusalem, by the power of mine arm, that I might raise up unto me a righteous branch from the fruit of the loins of Joseph.
26 Wherefore, I the Lord God will not suffer that this people shall do like unto them of old.
27 Wherefore, my brethren, hear me, and hearken to the word of the Lord: For there shall not any man among you have save it be one wife; and concubines he shall have none;
28 For I, the Lord God, delight in the chastity of women. And whoredoms are an abomination before me; thus saith the Lord of Hosts.
29 Wherefore, this people shall keep my commandments, saith the Lord of Hosts, or cursed be the land for their sakes.
30 For if I will, saith the Lord of Hosts, raise up seed unto me, I will command my people; otherwise they shall hearken unto these things.
31 For behold, I, the Lord, have seen the sorrow, and heard the mourning of the daughters of my people in the land of Jerusalem, yea, and in all the lands of my people, because of the wickedness and abominations of their husbands.
32 And I will not suffer, saith the Lord of Hosts, that the cries of the fair daughters of this people, which I have led out of the land of Jerusalem, shall come up unto me against the men of my people, saith the Lord of Hosts.
Or even HERE:
1 Timothy 3:2-3
2. Now the overseer must be above reproach, the husband of but one wife, temperate, self-controlled, respectable, hospitable, able to teach,
3. not given to drunkenness, not violent but gentle, not quarrelsome, not a lover of money.1 Timothy 3:12
A deacon must be the husband of but one wife and must manage his children and his household well.Titus 1:6
An elder must be blameless, the husband of but one wife, a man whose children believe and are not open to the charge of being wild and disobedient.
DOCTRINE AND COVENANTS
OF THE CHURCH OF JESUS CHRIST OF LATTER-DAY SAINTSSECTION 1325157, Emma Smith is counseled (commanded) to be faithful and true; 5866, Laws governing the plurality of wives are set forth.51 Verily, I say unto you: A commandment I give unto mine handmaid, Emma Smith, your wife, whom I have given unto you, that she stay herself and partake not of that which I commanded you to offer unto her; for I did it, saith the Lord, to aprove you all, as I did Abraham, and that I might require an offering at your hand, by covenant and sacrifice.52 And let mine handmaid, Emma Smith, areceive all those that have been given unto my servant Joseph, and who are virtuous and pure before me; and those who are not pure, and have said they were pure, shall be destroyed, saith the Lord God.53 For I am the Lord thy God, and ye shall obey my voice; and I give unto my servant Joseph that he shall be made ruler over many things; for he hath been afaithful over a few things, and from henceforth I will strengthen him.55 But if she will not abide this commandment, then shall my servant Joseph do all things for her, even as he hath said; and I will bless him and multiply him and give unto him an ahundredfold in this world, of fathers and mothers, brothers and sisters, houses and lands, wives and children, and crowns of beternal lives in the eternal worlds.