The Lenten season is noted by two very distinct liturgical omissions. Not even the hymn known as the Gloria (Glory to God in the Highest) nor the Alleluia verse sung before the Gospel is allowed during the entire 40 days of Lent.
Why is it like that?
First of all, the Gloria is a hymn that reminds us about the coming of the Lord using words from the angels at the birth of Christ. During Lent the Church returns in spirit to a time when the people of God were in exile, waiting for the Messiah to come and save them. It is the same season of expectation as is Advent, but instead of awaiting Christ’s birth from the womb of Mary, the Christians await Christ’s second “birth” from the womb of the sepulcher.
On the second hand, following this same spirit of exile, the Church joins with Moses and the Israelites as they wander in the desert for 40 years. It is a time of agony and sanctification, where the faithful join together to say, “How shall we sing the Lord’s song in a foreign land?” (Psalm 137:4). The word “Alleluia” is gotten from a Hebrew expression that means “praise the Lord” and is therefore omitted during Lent.
As a result of it, our focus in Lent is not about rejoicing, but in mourning our sins, looking at those things that take us away from an authentic relationship with God. Once these mourning are removed through prayer, fasting, and almsgiving, we would be able to rejoice again at Easter, for it is not only in Christ’s resurrection that we celebrate, but we also celebrate our own rebirth in the spirit.
Same as a woman experiencing labor groans in pain before birth, so the Christian people groan inwardly as we wait for adoption as sons, and the redemption of our bodies (Romans 8:23).