"For when a Roman thought himself to have a sufficient Provision of Children, in case his Neighbour who had none, should come and desire him to accommodate him with his Wife, that he also might have the benefit of Issue from his fruitful Woman; he had a lawful Power to lend her to him who desired her, either for a certain time, or else to loose the Bonds of Marriage, and consign her into the Hands of her Paramour for ever. But the Laconian had another rule: for it was allowable for him to afford the use of his Wife to any other that desired to have Children by her, and yet still to keep her in his House, and retain the Bond and Conditions of Marriage in the same force and vertue [virtue] as before"
[Source: "The Comparison of NUMA with LYCURGUS," at end of Paul Rycaut's translation of "THE LIFE OF Numa Pompilius," in John Dryden, ed., Plutarch's Lives: In Five Volumes. Translated from the Greek, By several Hands, 5 vols. (London: Jacob Tonson, 1716), 1: 203, in "Evidence For The Sexual Side of Joseph Smith's Polygamy," Comments by D. Michael Quinn on Session #2A "Reconsidering Joseph Smith's Marital Practices," Mormon History Association's Annual Conference, Calgary, Alberta, Canada, 29 June 2012 (unabbreviated version, revised during July)]