Hi, John - Brown does a good job on the history of attitudes toward sexuality. He doesn't address questions such as "What does human sexuality say about God?" -- other than the fact that most cultures have portrayed God as something of a prude and a misogynist. For example, from a female perspective, what does it say about God (and us) that female human beings have organs of pleasure as well as organs of reproduction, when female pleasure seems unrelated to either evolution or reproduction? 

These are questions asked by evolutionary biologists. In my opinion, they would have to form the basis for any theology of human sexuality.