Together with Baptism and the Eucharist, the sacrament of Confirmation completes the "Sacraments of Christian Initiation," as such, the unity of these rites must be safeguarded. The final completion of Baptismal Grace is essentially completed by the sacrament of Confirmation. Through the sacrament of Confirmation, the baptized are more perfectly bound to the Church thus enriched with a special strength of the Holy Spirit (see the Catechism of the Catholic Church, Part Two, Section Two, Chapter One, Article 2.I).
With the sacrament of Confirmation, the baptized now become a true witness of Christ, and charged with a higher obligation to spread and defend the faith through word and deed. The seeds of the sacrament of Confirmation can be traced back to the Acts of the Apostles, specifically Acts 8:14-17, which states that "Now when the apostles in Jerusalem heard that Samaria had accepted the word of God, they sent them Peter and John, who went down and prayed for them, that they might receive the Holy Spirit, for it had not yet fallen upon any of them; they had only been baptized in the name of the Lord Jesus. Then they laid hands on them and they received the Holy Spirit."
One of the immediate images of the Sacrament of Confirmation is the laying of hands, as mentioned in Acts 8:14-17, and 19:6. While this is obviously important, the essential element of the Sacrament of Confirmation is the anointing of the confirmand (the one who is being confirmed) with an aromatic oil known as chrism, accompanied by the words "Be sealed with the Gift of the Holy Spirit."
This seal is the consecration, representing the final safeguarding by the Holy Spirit of the graces conferred during the Rite of Baptism.