We have to be very careful in taking specific passages that refer to polygamy without also considering them within the overarching story of marriage in Scripture. First, we have the command of God to Adam and Eve, using the singular "wife":
Gen 2:24 Therefore a man shall leave his father and his mother and hold fast to his wife, and they shall become one flesh. (ESV)
That is the normative prescription for marriage that carries throughout the Bible. Then we come across the first polygamist in the Bible:
Gen 4:19 And Lamech took two wives. The name of the one was Adah, and the name of the other Zillah.
...
Gen 4:23 Lamech said to his wives: “Adah and Zillah, hear my voice; you wives of Lamech, listen to what I say: I have killed a man for wounding me, a young man for striking me.
Gen 4:24 If Cain's revenge is sevenfold, then Lamech's is seventy-sevenfold.” (ESV)
It is important to note that Lamech was very wicked, which implies that his having more than one wife is morally wrong, as it is not in keeping with the command God gave to Adam and Eve. Then we have the seventh commandment and sex outside of marriage:
Exo 20:14 “You shall not commit adultery. (ESV)
Given what is stated in Gen 2:24, this would prohibit multiple wives and sexual partners. Jesus appeals to that commandment but shows what it really means:
Mat 5:27 “You have heard that it was said, ‘You shall not commit adultery.’
Mat 5:28 But I say to you that everyone who looks at a woman with lustful intent has already committed adultery with her in his heart. (ESV)
On a side note, this is because sin isn't necessarily an action; it's a matter of the heart, where all sin begins (Matt 15:18-19).
Then, regarding the kings of Israel:
Deu 17:17 And he shall not acquire many wives for himself, lest his heart turn away, nor shall he acquire for himself excessive silver and gold. (ESV)
What do we see with David? David took multiple wives and concubines, something the Law said he wasn't supposed to do, and his polygamy led to murder and the breaking up of his house. Never is polygamy condoned in the Bible and is often put in a negative light. Abraham's polygamy came with a high cost as well (Gen 16:11-12).
Jesus gives what is the normative teaching regarding marriage throughout Scripture:
Mar 10:5 And Jesus said to them, “
Because of your hardness of heart he wrote you this commandment.
Mar 10:6
But from the beginning of creation, ‘God made them male and female.’
Mar 10:7 ‘Therefore a man shall leave his father and mother and hold fast to his wife,
Mar 10:8 and the two shall become one flesh.’ So they are no longer two but one flesh. (ESV)
It is important to see that Jesus argues right back to creation as to the ideal for marriage. Paul also does so here, in speaking of marriage but also makes the parallel to Christ and the Church:
Eph 5:31 “Therefore a man shall leave his father and mother and hold fast to his wife, and the two shall become one flesh.”
Eph 5:32 This mystery is profound, and I am saying that it refers to Christ and the church. (ESV)
Paul's appeal to Gen 2:24 also includes the singular "wife." This is what Paul states is necessary for elders and deacons:
1Ti 3:2 Therefore an overseer must be above reproach,
the husband of one wife, sober-minded, self-controlled, respectable, hospitable, able to teach,
...
1Ti 3:12 Let deacons each be
the husband of one wife, managing their children and their own households well. (ESV)
Tit 1:5 This is why I left you in Crete, so that you might put what remained into order, and appoint elders in every town as I directed you—
Tit 1:6 if anyone is above reproach,
the husband of one wife, and his children are believers and not open to the charge of debauchery or insubordination. (ESV)
Lest anyone think that is only for leaders in the Church, that is also seen regarding all believers in general:
1Co 7:1 Now concerning the matters about which you wrote: “It is good for a man not to have sexual relations with a woman.”
1Co 7:2 But because of the temptation to sexual immorality,
each man should have his own wife and each woman her own husband.
1Co 7:3 The husband should give to
his wife her conjugal rights, and likewise the wife to
her husband. (ESV)
Notice that once again Paul is speaking in the singular regarding a man having a wife and a woman having a husband.
Putting that all together then, the Bible is prescriptive in teaching that marriage is between one man and one woman, and that is the only morally acceptable situation for sexual relations. God allowed some in the OT to have multiple wives and concubines, but that is descriptive, never prescriptive. And it is almost always, if not always, put in a negative light.
Here is a good article on this subject (where I got some of the above):
https://www.desiringgod.org/articles/why-did-god-allow-polygamy