The "Marriage" of the Theotokos

Actually it was just a betrothal, as Orthodoxy teaches. As an Eastern Catholic (and ex-Latin) who's converting to Orthodoxy recently pointed out to me, otherwise, Mary's surprise at Gabriel's prediction that she would have a child, wouldn't have made sense. Sometimes we're so familiar with a Scripture we don't really see it! This is why we need 2,000 years of Holy Tradition to help us.