The papal message is delivered annually to Catholics worldwide in the weeks leading up to Easter, known as the Lenten period.
This year's theme stems from the second chapter of the Bible's book of Colossians with a passage about baptism.
Benedict says Lent is a "most valuable and liturgical time" for Catholics and urges the faithful "to be guided by the word of God."
The Pope writes the period of Lent calls Christians to "retrace the steps of Christian initiation." Benedict says through baptism, believers are moved to free themselves from "the burden of material things."
The Pope stresses the ritual of fasting during Lent. He describes it as a means to overcome selfishness. Benedict tells Catholics that fasting enables Christians to be more open to the needs of others.
He also warns of the "greed of possession" and the "idolatry of goods," saying it undermines the importance of God.
The Pope urges Catholics to seek prayer during the Lenten season for a closer relationship with God and to understand his words.
Lent is observed by Roman Catholics in the 40 days before Easter and begins tomorrow on Ash Wednesday.