Mark is a very interesting writer, and I suggest that you wander over to his blog site, through the link below to a particular article of his, to see what I mean about interesting.
In the particular article linked here, he writes about Our Lady of Guadalupe. Mariology is a tough pill for our brother and sister non Catholic Christians to follow, about as hard as it is for those who do not believe in Christianity. But, in this particular article, Mark writes about the science around the apparition and the history of the time, when Mary appeared in 1531 in Mexico to a humble man Juan Diego.
Certain things of the time relate to her appearance, as do certain miraculous pieces of physical evidence. I won't spoil it for those of you who might have the interest to follow the link above, but I suggest that it would be well worth your while to see what he has to say. Though I have always believed that Mary appeared as what we know as Our Lady of Guadalupe, but I had no idea how deep the symbolism, and the evidence ran about this apparition.