[Women] have, of course, still to be more careful in sexual relations, for all the contraceptives. Mistakes are damaging physically and socially (and matrimonially). But they are instinctively, when uncorrupt, monogamous. Men are not. . . . . No good pretending. Men just ain’t, not by their animal nature. Monogamy (although it has long been fundamental to our inherited ideas) is for us men a piece of ‘revealed’ ethic, according to faith and not to the flesh. Each of us could healthily beget, in our 30 odd years of full manhood, a few hundred children, and enjoy the process. Brigham Young (I believe) was a healthy and happy man. It is a fallen world, and there is no consonance between our bodies, minds, and souls.
However, the essence of a fallen world is that the best cannot be attained by free enjoyment, or by what is called ‘self-realization’ (usually a nice name for self-indulgence, wholly inimical to the realization of other selves); but by denial, by suffering. Faithfulness in Christian marriage entails that: great mortification. For a Christian man there is no escape. Marriage may help to sanctify & direct to its proper object his sexual desires; its grace may help him in the struggle; but the struggle remains. It will not satisfy him — as hunger may be kept off by regular meals. It will offer as many difficulties to the purity proper to that state, as it provides easements. No man, however truly he loved his betrothed and bride as a young man, has lived faithful to her as a wife in mind and body without deliberate conscious exercise of the will, without self-denial.
Too few are told that — even those brought up ‘in the Church’. Those outside seem seldom to have heard it. When the glamor wears off, or merely works a bit thin, they think they have made a mistake, and that the real soul-mate is still to find. The real soul-mate too often proves to be the next sexually attractive person that comes along. Someone whom they might indeed very profitably have married, if only –. Hence divorce, to provide the ‘if only’. And of course they are as a rule quite right: they did make a mistake. . .
–The Letters of J.R.R. Tolkien, No 43 ‘From a letter to Michael Tolkien 6-8 March 1941’
[read pt 4]