Mother Mary

Paul McCartney sang: 

When I find myself in times of trouble, Mother Mary comes to me
Speaking words of wisdom, let it be 
And in my hour of darkness she is standing right in front of me
Speaking words of wisdom, let it be
But he wasn’t talking about the mother of Jesus. He was talking about his own deceased mom, and the dream of her giving him advice as his band went through the turmoil of 1969. 

The other mother Mary, from the Bible, is a figure about whom we don’t know nearly enough. She stayed mostly in the background, and what is most consistently attached to her is the very thing that most would be skeptical of: the virgin-conception of God’s son. 

But we know a few other things and they turn out to be important. She seems to have journeyed all the way down to Egypt while Jesus was a newborn. And when bringing the child to the temple a strange old man gave her an erie prediction that a “sword would pierce” her heart too. 

Who was she? And why is it important?