"As we approach Advent, we must be aware that we are approaching the One who sends us on mission. In general, He sends all of us on mission to proclaim the joy that is based in Him. But, on a more personal level, He gives each and every member of His Body a mission to live that joy in a unique way. "


I don't know who wrote that.  It is written by way of introduction for Fr. Robert Barron.  Here it the webpage.
http://www.wordonfire.org/WoF-Blog/WoF-Blog/December-2010/Advent--Discerning-the-Will-of-God.aspx


Joy is underrated.  It is one of the fruits of the Holy Spirit!  


"In contrast, the fruit of the Spirit is love, joy, peace, patience, kindness, generosity, faithfulness, gentleness, self-control.  Against such there is no law."  Galations 5:22-23


The rest are virtues we usually think about trying to achieve.  Joy, well, we tend to think if it as a side effect.  I like the quote, because it directs us to aspire to joy.  


In a recent conversation a friend said, "I know its Advent, and I am not supposed to be joyful but..."  We are supposed to be joyful!  Even in Advent!  'Penitential season' does not mean 'season of unhappiness.'  We must repent of our sin- but with joy in the knowledge of forgiveness.  During penitential seasons we are supposed to increase in prayer, fasting and almsgiving.  Which of these saps joy?  None should.  The reason we do these things is to grow closer to God.  Growing closer to God means living in His Spirit.  The fruits of the Spirit are love, joy, peace, patience, kindness, generosity, faithfulness, gentleness, and self-control.  


"Yes, and I ask you also, my true yokemate, to help them, for they have struggled at my side in promoting the gospel, along with Clement and my other co-workers, whose names are in the book of life.  Rejoice in the Lord always. I shall say it again: rejoice!"  Philippians 4:3-4


In this letter, Paul acknowledges the hardship, but the theme is joy.  This is the our mission: Rejoice!  Aspire to joy.


Prepare for the Lord joyfully!  


and, because I love William Byrd:
http://www.youtube.com/watch?v=lg00ccXEdyw&feature=related