"Not one word of the gospel is about Mary,"

"...but everything about Mary points to Christ." - Fr. Thomas Hopko 

I listened to a lovely podcast recently, Mary the Mother of All Believers, which explains the idea that she is the icon of all believers. It's not long, so I'd encourage you to go listen. (The podcast linked above is Fr. Hopko on the magnificat, which is also quite good, but much longer.)