Supreme Court on Polygamy

Here is part of a decision on marriage:

...on the 8th of December, 1788, after the passage of the act establishing religious freedom, and after the convention of Virginia had recommended as an amendment to the Constitution of the United States the declaration in a bill of rights that "all men have an equal, natural, and unalienable right to the free exercise of religion, according to the dictates of conscience," the legislature of that State substantially enacted the statute of James I., death penalty included, because, as recited in the preamble, "it hath been doubted whether bigamy or polygamy be punishable by the laws of this Commonwealth." (12 Hening's Stat. 691). From that day to this we think it may safely be said there never has been a time in any State of the Union when polygamy has not been an offence against society, cognizable by the civil courts and punishable with more or less severity. In the face of all this evidence, it is impossible to believe that the constitutional guaranty of religious freedom was intended to prohibit legislation in respect to this most important feature of social life. Marriage, while from its very nature a sacred obligation, is nevertheless, in most civilized nations, a civil contract, and usually regulated by law. Upon it society may be said to be built, and out of its fruits spring social relations and social obligations and duties, with which government is necessarily required to deal. In fact, according as monogamous or polygamous marriages are allowed, do we find the principles on which the government of the people, to a greater or less extent, rests.

https://scholar.google.com/scholar_case?case=1104642225155375579&q=meaning:+separation+of+married+persons&hl=en&as_sdt=6,24