As academic biblical scholars, we wish to clarify that the biblical texts do not support the frequent claim that marriage between one man and one woman is the only type of marriage deemed acceptable by the Bible’s authors.Very interesting article by Robert Cargill and two colleagues. The Bible, particularly Leviticus which is the book usually cited, reflects Jewish laws from thousands of years ago - and the views of the vast majority of Jews have evolved since then.
Many sections of the Hebrew Bible support polygamy, and polygamy was not banned in Judaism until quite late: David's many wives are famous, and Herod the Great was a polygamist in the Macedonian tradition.
Leaving aside Levirate Marriage - by the early Middle Ages a ceremony evolved where this was side-stepped by the wife refusing her late husband's brother - polygamy was not prohibited in Ashkenazi Judaism until around AD 1000, by a ruling of Gershom ben Judah (Rabbeinu Gershom). [Actually theoretically an Ashkenazi Jew may take a second wife if one hundred rabbis sign off on it, but I know of no example of this being tried].
In Sephardi and Mizrahi Judaism polygamy was accepted practice for far longer. Maimonides (Rambam, dies 1204) issued several rulings that allowed for polygamy. I can't find the reference, but in theory the Talmud allowed for up to four wives, although most women had their Ketubah state that the husband could not take a second wife.
Today Jewish polygamy is almost unheard of, but it continued to be occasionally practiced until the 19th century in Muslim countries.
For a humourous book exploring how ridiculous it is to try to impose Biblical laws today, I can't recommend this one enough: The Year of Living Biblically by A.J. Jacobs.