Conservative politicians in the U.K. and in the U.S.A. are fond of asserting that marriage has always been between one man and one woman. They rest their case on the Bible
Evangelical and Roman Catholic Christians in both countries agree with this point of view, and assert that the Christian teaching, based in Holy Scripture and/or the Tradition of the Church, is unchangeable.
Predictably neither the politicians, nor the the Church leaders get it right.
FOR EXAMPLE, in the biblical record Abraham had a wife and a concubine, Jacob had two wives, David had multiple wives and concubines, Solomon had many wives and many concubines.
AND IN THE CHRISTIAN TRADITION the leaders of the western European Church (Popes, Cardinals, Bishops) found many ways by which the Kings, Emperors and Princes of western Europe could set aside a wife (e.g. by the fiction of annulment), and then marry another.
IN MANY CASES the decisions of Popes, Cardinals and Bishops rested not on the bible or the tradition of the Church; but on the political alliances and allegiances of any given Pope.
Thus it was that the odious King Henry VIII of England had six wives.
He would have asserted that he had but three marriages.
He would have claimed that:
1. Catherine of Arragon was never his true wife since she had been previously married to his deceased brother Arthur, and therefore his marriage to her was void.
2, Anne Boleyn was his true wife, but he was a widower after she died ( by being beheaded at his command!).
3. Jane Seymour was his true wife, the mother of his longed-for male heir (Edward VI), but she died soon after giving birth to Edward.
4. His marriage to Ann of Cleves was a terrible mistake, and that he could legally set her aside because of a defect in the marriage contract.
5. Katherine Howard was never his true wife because of her alleged affairs (based on trumped up charges) - but in any case he was free to marry again after her death: (like Anne Boleyn by being beheaded at his command!).
6. Catherine Parr was a true wife.
So, via legal and (Roman Catholic) Church sanctioned "jiggery-pokery", Prince Hal could/would have claimed that his marriages to Anne B, Jane S, and Catherine P. were the only three which were "biblical and Christian"..
So much for Marriage - Biblical and Christian - One man, One woman.
That idea is a Biblical and Christian fiction.
The Bible and Christian history are replete with examples of marriages which modern Evangelical and Catholic Christians would denounce as being unacceptable.
and weep for the six noble women who were treated as mere chattels.