The short answer to the question raised by the title is, "Yes."
Now, I know that answer is provocative. Bear with me in this rather long post. I want to explain to you why, as a biblically conservative Christian, I believe the answer yes to the question in the title is true. But, I also want to explain why this answer does not make gay-marriage morally acceptable. Finally, I want to offer a surprising appeal: the church should get out of the wedding business.