Orson Pratt discusses the plural marriages of David and Solomon.
Orson Pratt, "Celestial Marriage," The Seer 1, no. 7 (July 1853): 106–107
David, being a man after God's own heart, took seven wives before he ascended the throne to reign over all Israel. He being a prophet was well qualified to govern and instruct a family in righteousness. He had more wives and children committed to him than many of his brethren because he was better qualified to lead them to salvation. After David had taken seven wives, the Lord thinking that he had not yet a sufficient number, gave into his bosom all of Saul's wives. (2 Sam. 12:8.) What is the secret of the Lord's being so anxious for David to have so many wives? Because, he, being a man after God's own heart, would he more likely to save his wives and children, than many others of Israel who were less faithful.
But when David turned from his righteousness and took Uriah's wife, the Lord now considered him no longer worthy of his wives and He gave them to his neighbor. He was informed by the Lord through Nathan, the Prophet, that if Saul's wives and that which He had already given to him "had been too little," "I would moreover" he says, "have given unto thee such and such things;" (2 Sam. 12:8.) clearly intimating that, He, the Lord, would have given him more, lawfully, if he had been faithful. But now he had forfeited all that he had got. Saul, though he had been a prophet, afterwards transgressed and rendered himself unwoithy of his kingdom — unworthy of his wives — and unworthy of even life itself. Wives and children are among the greatest blessings bestowed upon the righteous. He, therefore, that receives these blessings and continues faithful, will be counted worthy to receive more; but he that is unfaithful will have taken from him even that which he has. This was the case with Saul and David; their wives were taken from them. David by taking that which did not belong to him, lost all his own.
God raised up Solomon to sit upon the throne of Israel; and He appeared unto him twice and gave him great wisdom above all others and the Lord was with him, and magnified him exceedingly before all Israel, and hearkened unto his prayer and filled the temple which he built with a cloud of glory, and caused fire to descend from Heaven to consume the sacrifice. This great man was much better calculated to train up children in the way that they should go than any other man living, for God had given him greater wisdom; hence he had seven hundred wives and three hundred concubines. (1 Kings, 11.) But even this wise man, turned away from the Lord, by taking wives from among surrounding nations who were idolaters which thing the Lord had expressly forbidden. (See verses 1, 2.) Solomon was not condemned for marrying many wives of his own nation; but having transgressed the strict commandment of God in marrying out of his nation, he was left unto himself and turned away after the idolatrous gods of his wives; and God rent the kingdom in twain in the days of his son, and gave ten tribes to another not of his seed.