Confirmation, together with Baptism and Eucharist, form the Sacraments of Initiation that are all intimately connected. In the Sacrament of Confirmation, the baptized person is "sealed with the gift of the Holy Spirit" and is strengthened for service to the Body of Christ.
Those who believed in the Apostles' preaching were baptized and received the Holy Spirit through the laying on of hands. The Apostles baptized believers in water and the Spirit. Then they imparted the special gift of the Spirit through the laying on of hands. "'The imposition of hands is rightly recognized by the Catholic tradition as the origin of the sacrament of Confirmation, which in a certain way perpetuates the grace of Pentecost in the Church'" (CCC, no. 1288, citing Pope Paul VI, Divinae Consortium Naturae, no. 659).