Hieros Gamos

I'm reading the Da Vinci Code right now and at one point they point talk about an ancient ritual Hieros Gamos. Now it's kind of crazy and wild, remember the movie Eyes Wide Shut with Tom Cruise and Nichole Kidman, well it's sort of like that but of coarse that was a movie and dramatized.
So it's a sacred sex ritual were man experiences completeness through the sacred carnal knowledge of the feminine. The only reason it caught my attention was because when I was at Trinity one of our profs, actually our favorite psychology prof. Did his doctoral dissertation on spirituality and sexuality. He even taught the class I think it was called, "Sexuality and Spirituality 300's," it was like sex education at University quite entertaining, everyone looked forward to taking this class.
The rumor was that he had this whole thesis written on man and woman becoming closer to God through their union. The idea being God is neither female or male but one entity. So when you're married you're complete and can relate to God better.
I never actually read the thesis I think I heard him speak about it once and I always wondered what he was talking about.
So now this book seems to be touching on some of these same principles and so I'm heading to the internet to read more about this Hieros Gamos, Greek for sacred marriage.