The passage from Luke 1:46-55 is known as "The Magnificat" or "The Song of Mary." I like to look at a passage of scripture in context of the contemporary situation. By "contemporary situation" I am referring to the events, feelings, emotions, stressors, and all other life experiences that are going on at the time.
In this case, Mary was a single unwed teenaged mother-to-be. As bleak as this situation would be for a girl in the 21st century USA, think of the context around Mary's pregnancy. Her pregnancy was beyond socially unacceptable -- it could have resulted in punishment up to and including death.
But despite this, Mary is grateful, and has faith that God has selected her for a marvelous task. She did, after all, know that she was a virgin, so I suppose that could explain why she believes it was an "immaculate conception." But that still doesn't explain how easily she seemed to accept this burden as a joy.
Who knows, maybe she cried, complained, and carried on to God, wondering how God could do something like this to her. Perhaps she was upset like many of us are when dealt a difficult hand to play. But if she was complaining, the sciprtures don't mention it.
What the scripture tells us is that she was grateful for the chance to serve in her own way. Whether she was grateful right away or grateful after a temper tantrum isn't as important as her final disposition.
Isn't this a good lesson for us to take away? Can we not learn from Mary how to find the blessing in the context of where we are in life? I sometimes dislike a situation I'm placed in. As a pastor, not everything I deal with is pleasant, and many situations I find myself in are very awkward to deal with. I just hope that I can thank God for those things he sends my way and see them as an opportunity to serve God's people -- even if it's in a way I wouldn't have asked for.