If I had to place my finger on the most contentious issue the secular world takes with Christian ethics is its stance on sexuality. Without a doubt, the Old and New Testaments condemn certain sexual relations in the strongest terms available. Be it adultery, sex out of wedlock, beastiality, or homosexual sex. The bible makes moral judgements regarding sexuality. Whether one chooses to debate this point is not really at issue in this post. What I would like to discuss is how, on secular ethics, or even atheistic naturalism is sexual immorality determined or discovered, if in fact it exists.
Strictly speaking, I’m not looking for specific examples. What I would like to see is by what measure within the secular or atheistic worldview is sexual immorality graded, what is the standard used? Of course there will be some who will assert no sexual act can be judged as moral or immoral, but I don’t think they truly believe it in practice and are merely defending philosophical turf.
So to my secular and naturalistic atheist readers, how would you judge a sex act moral or immoral? When answering, keep in mind I will not offer a rebuttal of moral grounding proper (I.e., “how can you say anything is moral or immoral without a transcendent standard…”), and would urge my fellow Christian readers to not go down that path. I would like the discussion to carry out under the moral framework of the secularist or naturalistic atheist. A coherent standard will not allow for special pleading or contradictions and this should be bourne out in the answers.