Yes, multiple wives is mentioned in the old testament. It is a common cultural aspect of agrarian societies with little medicinal knowledge. It also occurs in some nomadic culturers where the environment/neighbors were hostile enough to reduce the number of men. In agrarian cultures it was a method of generating sufficient 'hands' to till the land and the multiple wives offset the deaths that would occur due to complications during child birth. It began leaving the cultures as people started taming the land, reducing the hostile wildlife and learning better medicinal/childbearing techniques that resulted in lower infant and woman fatalities.
Therefore, society has decreed that poligamy is no longer necessary for maintaining a living or family line. Hence, laws that punish those who violate the cultural mores.
History lesson complete