The Lenten Season
Lent is one of two great seasons of preparation and penance, Lent leads up to Easter.  The other being Advent, which leads up to Christmas.
 
Starting on Ash Wednesday and consisting of 40 days, excluding Sundays, Lent was traditionally a season of preparation for new converts who were to be baptized on Easter Sunday.

The number of days comes from gospel accounts of Jesus' 40 days of testing in the wilderness.  Lent is generally a time for all Christians to strengthen their faith, with emphasis on prayer, fasting, acts of penance and mercy.
Why Do Christians Observe Lent?
If the Christian calendar is an instrument for faith formation, what ought to be formed in us during Lent?  Romans 6:3 says:
"Do you not know that all of us who have been baptized into Christ Jesus were baptized into his death?"  As preparation for baptism and renewal of baptism we are called to live as those who are being baptized in Christ's death, that being raised with him "we too might walk in newness of life" (Rom. 6:4).  And being raised with Christ we are to set our minds on "things that are above, not on things that are on earth" (Colossians 3:2).  Thus, Lent is a season to practice laying aside "every weight and sin that clings so closely," that we might "run with perseverance the race that is set before us, looking to Jesus the pioneer and perfector of our faith..."(Hebrews 12:1b-2a).
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