Mary is the hero of the pondering stories in the Gospels. While everyone around her is stirred and amazed, she ponders all these things in her heart (Luke 2:19). Some translations use treasured. I like that too, but it has the danger of communicating nostalgia to us modern readers, as if Mary kept these memories of angels and wise men to look back on and treasure. It doesn’t mean that. It means that she took in all the data of that moment and let it into her heart and kept it there so it might transform and change her.