Traditional Christian teaching on sex does not mesh with the original writings of the Bible set in their historical and cultural context. That is one premise in this important book by Philo Thelos (Divine Sex: Liberating Sex from Religious Tradition - click on title above). The book will shock card-carrying evangelicals or fundamentalists but simply can't be ignored. Again, my conservative Christian friends will think I've gone overboard with my endorsement of this book. The few I've shared it with think anyone who accepts it is ignoring the "clear" teaching of scripture and just wants to be free from moral constraints.
The book is compelling because the author is from a conservative church background and maintains a high view of scripture. He advocates for sound Bible study methods (original language, meaning, and historical context is key to understanding) in the vein of scholars like Gordon Fee. So, what's the controversy? He challenges traditional moral understanding about adultery, sexual immorality, and marriage fidelity with a sound Biblical argument.
For instance, have you ever wondered why polygamy, concubinage, and other multiple sexual relationships are practiced by Biblical heros without a word of censure from God? Did you know that if Bethsheba, with whom David had an adulterous liaison, was single, he wouldn't have committed adultery? In the NT, the word translated "sexual immorality" or "fornication" is the Greek word "porneia", which refers to illicit and idolatrous practices as defined by the Torah and does not refer to singles sexuality, oral sex, masturbation, erotic writings, or viewing graphic depictions of the human body.
The main ethic that can be derived from the Bible regarding sexual practice is a love ethic. In your sexual life, do not harm another but love and respect your neighbor. Adultery is wrong because it takes what belongs to another (sexual theft) or breaks a commitment made to another. If in a marriage, a couple allows one another to engage in other relationships that don't steal what belongs to another, those relationships don't fit the Biblical definition of adultery. Monogamy and abstinence from sex until marriage is not demanded by the Scriptural definitions of porneia. The book Divine Sex convincingly makes this case and challenges the traditional faulty interpretations of sexual morality in the church today.