The prophets of the Old Testament foretold that God’s Spirit would rest upon the Messiah to sustain his mission. Their prophecy was fulfilled when Jesus the Messiah was conceived by the Spirit and born of the Virgin Mary. The Holy Spirit descended on Jesus on the occasion of his baptism by John. Jesus’ entire mission occurred in communion with the Spirit. Before he died, Jesus promised that the Spirit would be given to the Apostles and to the entire Church. After his death, he was raised by the Father in the power of the Spirit.
Confirmation deepens our baptismal life that calls us to be missionary witnesses of Jesus Christ in our families, neighborhoods, society, and the world. . . . We receive the message of faith in a deeper and more intensive manner with great emphasis given to the person of Jesus Christ, who asked the Father to give the Holy Spirit to the Church for building up the community in loving service.
~from the United States Catholic Catechism for Adults (Via: usscb.org)
The sacrament of confirmation completes the sacrament of baptism. If baptism is the sacrament of re-birth to a new and supernatural life, confir- mation is the sacrament of maturity and coming of age. The real confession of Christ consist in this 'that the whole man submits himself to Truth, in the judgment of his understanding, in the submission of his will and in the consecration of his whole power of love . . . To do this, poor-spirited man is only able when he has been confirmed by God's grace'
This confirmation in the power of the Holy Spirit leading to a firm profession of faith has always been the particular effect which Catholic tradition has ascribed to the sacrament. It is effect which complements and completes that of baptism.
THE CHURCH TEACHES
Confirmation is a true sacrament instituted by Christ and different from baptism. It is administered by laying-on of hands and anointing with chrism accompanied by prayer. The chrism is blessed by the bishop and the bishop administers the sacrament. All baptized persons can and should be confirmed. The effect of the sacrament of confirmation is to give strength in faith and for the confession of faith and to impress an indelible character.