Certainly a theme during this season is joy and gladness. Office parties, family gatherings, school shows, decorating all bring a certain happiness in our lives. However, there is another reason, a greater reason, why we are to be filled with joy and gladness.
In the midst of sadness and distress, anxiety and worry, pain and suffering and all of the realities of our lives, Advent helps us to realize that God is with us - He is Emmanuel; and joy in our hearts is the best sign to acknowledge His presence.
In other words, the His presence is the cause of our joy. Zephaniah urges the people to rejoice because “the Lord… is in your midst.” And Paul tells the Philippians he wants them to be happy, because “the Lord is very near.” The joy that this world cannot give is the joy that comes from believing our closeness with God and the certainty of his love for you and me. This joy, with all its laughter and smiles, can only become a reality when Christ resides in our hearts.
Now here is the really Good News - that we can still rejoice (gaudate), and shout for joy, and be glad even while fulfilling our responsibilities as Christians. Our world may say otherwise, but the message for us is that our joy will be complete when we turn away from sin and turn towards Christ especially in following His commandment of loving God and loving one another.
In general, being kind and generous, sharing our resources with others, showing concern for others and being just and merciful in all our dealings with others will in fact make us happy.
But only when those actions coincide with our faith that says God is indeed in with us. Therefore, cannot but sing and shout for joy, giving praise and declaring the greatness of God's Holy name.