2 Samuel - Chapter 3
This chapter begins with David failing to follow God's laws. There is a list of six sons born to David in Hebron, each one having a different mother.
In Deuteronomy 17 God had given this command:
“When you come to the land which the Lord your God is giving you, and possess it and dwell in it, and say, ‘I will set a king over me like all the nations that are around me,’ you shall surely set a king over you whom the Lord your God chooses; one from among your brethren you shall set as king over you; you may not set a foreigner over you, who is not your brother. But he shall not ... multiply wives for himself, lest his heart turn away."
Jesus gives his answer on marriage to more than one wife in Matthew 19:
The Pharisees also came to Him, testing Him, and saying to Him, “Is it lawful for a man to divorce his wife for just any reason?” And He answered and said to them, “Have you not read that He who made them at the beginning ‘made them male and female,’ and said, ‘For this reason a man shall leave his father and mother and be joined to his wife, and the two shall become one flesh’? So then, they are no longer two but one flesh. Therefore what God has joined together, let not man separate.” They said to Him, “Why then did Moses command to give a certificate of divorce, and to put her away?” He said to them, “Moses, because of the hardness of your hearts, permitted you to divorce your wives, but from the beginning it was not so. And I say to you, whoever divorces his wife, except for sexual immorality, and marries another, commits adultery; and whoever marries her who is divorced commits adultery.”