I read an interesting article to the effect that Good Friday is the most Christian holiday not because it is uncorrupted by the secular world, but because it has the most pure origins. (Christmas was moved to where it was to get people to stop celebrating the Winter Solstice. Easter is the Spring Equinox and of course the Jewish Passover, etc.) I'm linking the article, but I'm actually linking the reproductin of the article that is on a friend's livejournal: http://www.livejournal.com/users/je_reviens/557718.html#cutid1