Polygamy has been in the news as a result of Warren Jeffs and the child custody case that's become so prevalent in the news. As a result a lot of people are asking questions about polygamy, questions like "Is this not consistent with what the founder of the Mormons taught?" and "Isn't there some kind of a precedent for polygamy in Scripture?"
The answer to the last question is no. The ideal pattern of monogamous marriage of one woman and one man was established early in Genesis. Remember the text that says "For this reason a man will leave his father and mother and be united to his wife and they will become one flesh." This very passage was quoted by Jesus and Paul in defense of the sacredness and exclusivity of monogamous marriage.
Not only that, but the Bible explicitly condemns the polygamy of Old Testament kings. The New Testament, in like fashion, says that elders and deacons are called to be the husband of but one wife. Just as the requirements for church leaders set the standards of morality and maturity for all believers, so the admonition against polygamy for the kings of Israel demonstrates the danger of this kind of practice.
God's distain for polygamy is clear in its consequences. The Old Testament reveals the strife and the temptations that accompany this kind of practice. Of course Solomon is the quintessential example. His legacy of faithfulness was compromised because of his polygamous behavior. Despite world-renowned wisdom his peaceful, prosperous rule ended in scandal and civil strife. Why? The Bible is emphatic. It's because his wives turned his heart after other gods.
There is no standard in civilization, there is no context in the canon of God's Word, that gives any out for this kind of behavior. It simply is not sanctioned in Scripture. The fact that the Bible gives examples of people who defied His will is simply a way of saying that the Bible is not airbrushed. It provides reality in its naked deformity, with all its warts and moles and wrinkles. It tells it like it is. But the fact that the Bible has a narrative about something doesn't mean that the Bible sanctions it. You go to the didactic, the teaching portions of Scripture, you see very clearly that this is a behavior that leads to all kinds of problems. We see this now front and center in the news, and for people who want to take this as an opportunity to besmirch the Scripture, we need to be ready to give an answer and that, again, is the purpose of the ministry. It is to help you to become equipped so that you can give an answer, a reason for the hope that lies within you, with gentleness and with respect.