Polygamy : from wiki
Biblical practice
See also: Pilegesh
Multiple marriage was considered a realistic alternative in the case of famine, widowhood, or female infertility[61] like in the practice of levirate marriage, wherein a man was required to marry and support his deceased brother's widow, as mandated by Deuteronomy 25:5–10. Despite its prevalence in the Hebrew bible, scholars do not believe that polygyny was commonly practiced in the biblical era because it required a significant amount of wealth.[62]
Polygyny continued to be practised well into the biblical period, and it is attested among Jews as late as the second century CE.[63]
—Michael Coogan, God and Sex. What the Bible Really Says.
The Torah, Judaism's central text, includes a few specific regulations on the practice of polygamy, such as Exodus 21:10, which states that multiple marriages are not to diminish the status of the first wife (specifically, her right to food, clothing, and conjugal relations). Deuteronomy 21:15–17, states that a man must award the inheritance due to a first-born son to the son who was actually born first, even if he hates that son's mother and likes another wife more;[64] and Deuteronomy 17:17 states that the king shall not have too many wives.[65] The king's behavior is condemned by Prophet Samuel in 1 Samuel 8. Exodus 21:10 also speaks of Jewish concubines. Israeli lexicographer Vadim Cherny argues that the Torah carefully distinguishes concubines and "sub-standard" wives with prefix "to" (lit. "took to wives").
Polygamy was practiced in many sections of Hindu society in ancient times. There was one example of polyandry in the ancient Hindu epic, Mahabharata, Draupadi marries the five Pandavabrothers. Regarding polygyny, in Ramayana, father of Ram, King Dasharath has three wives, but Ram has pledged himself just one wife.
The Hindu god, Lord Krishna, the 9th incarnation of the Hindu god Vishnu is supposed to have had 16,108 wives at his kingdom in Dwarka. In the post-Vedic periods, polygamy declined in Hinduism, and is now considered immoral,[57] although it is thought that some sections of Hindu society still practice polygyny, in the areas of India.