The word "Lent" literally means "spring" in English, but such a literal translation merely refers to the approximate time of year that this liturgical season occurs, not to its theological significance. Lent originally developed as a preparation for the Christian Passover, and it took place on the Saturday before Easter Sunday as well as on Easter. From its earliest inception, Lent was characterized both by a fast and by a period of final instruction for baptismal candidates, who would subsequently be baptized on Easter.
Lent would continue to keep its role as both a time of fasting for Christians and a preparation for baptism throughout the first several centuries of Christianity, but its length of time would gradually broaden. In the 2nd century, the Paschal fast before Easter lengthened from a one-day to a two-day fast (the Friday and Saturday before Easter). By the 3rd century, the period of Lenten preparation extended to the six days before Easter, and the fast also extending throughout these six days, though Friday and Saturday still held special significance for the Church. Towards the mid 4th century, there is clear evidence that the period of Lent had extended from six days to six weeks (or 40 days, if you calculate these days in a certain way), with the last week, which now observed Friday as a special day commemorating the crucifixion of Jesus (Good Friday), still maintaining a distinct place in the season. The reasons for expanding Lent to 40 days are unclear, but it is certainly possible that the number "40" was meant to parallel other Biblical events such as the 40 years spent by the Hebrews wandering in the wilderness and the 40 days in which Jesus was tempted by Satan. This 40 day period is still observed by the Church today, beginning with Ash Wednesday and ending with the Saturday before Easter (the Sundays of Lent are excluded from this 40-day calculation).
Although Lent is no longer associated explicitly with a period of baptismal preparation, it continues to be a season of discipline and self-reflection as we meditate on the difficult path Jesus followed to the cross and evaluate our lives in relation to how well we have followed in his footsteps. In a sense, Lent functions as a "yearly check-up," a chance for those of us who call ourselves "Christians" to examine our lives and evaluate our attempts to live up to the Christian name. Truthfully, if we do this, we will discover that we have failed to live up to the standards of discipleship that Jesus proclaimed and modeled in his own life. Yet even though Lent shows us that we all have much work to do to live as Jesus called us to live, the purpose of Lent is not to force us to dwell on our sinfulness and failures; rather, Lent is a sacred time that God has inserted into our temporal lives, a time in which God reminds us that there’s always an opportunity to start over, to take out a new lease of life. The challenge we as Christians face during this time of year is to approach Lent not as a litmus test but as a gift from above, a gift in which we can find the power to stop living in fear of failure or condemnation or death, and to start living as God intended us to live, in gratitude to the God who is our Creator, Redeemer, and Sustainer.