The biggest problem with this book is it doesn't really use scripture to prove the author's beliefs, which really amount to any consensual sex is approved, even when it's sex outside of the marriage partnership. A lot of suppositions are made about why the Bible forbids adultery (lack of condoms and birth control) but the author does nothing to prove his case. However, I pretty much gave up trying to find any truth in the author's beliefs when, attempting to justify wife-swapping, he asks, wouldn't it be a sin NOT to share ones wife if they both want to explore sex outside of their marriage? Really? A sin not to commit adultery? Sigh.