If I had a top ten list of biblical acts of faith, I believe that the shear act of faith that Mary displayed when told that she was to carry Jesus had to make at least one or two on my list. Just think about it, here you have a young teenage girl on the verge to being wed and being told one day by an Angel that she would be practically carrying in her womb the author of this universe. Just thing about that, that's huge. It took a huge leap of faith to even believe that it were to be possible as