“Only a little over a century ago, in 1905, a judge in a family case could confidently opine that the function of the judges was “to promote virtue and morality and to discourage vice and immorality.”  So the purpose of the law was the enforcement of morals. And that morality was, of course, Christian. In 1910, the Divisional Court had to consider whether a landlord was entitled to recover the unpaid rent on a flat let to a woman who was the mistress of the man who actually paid the rent. The decision was that the rent was not recoverable. There was evidence that the woman was in fact a prostitute and using the flat for purposes of prostitution, but that was not the basis of the decision. Darling J described her as “an immoral woman, being the kept mistress of a certain man” and the rent paid by him as “the price of her immorality”. He continued:
“I do not think that it makes any difference whether the defendant is a common prostitute or whether she is merely the mistress of one man, if the house is let to her for the purpose of committing the sin of fornication there. That fornication is sinful and immoral is clear. The Litany speaks of “fornication and all other deadly sin,” and the Litany is contained in the Book of Common Prayer which is in use in the Church of England under the authority of an Act of Parliament.”
 Constantinidi v Constantinidi and Lance  P 253, 278, per Stirling LJ.
 Upfill v Wright  1 KB 506.