The Sacrament of Confirmation
The sacrament of Confirmation is necessary for the completion of baptismal grace. For "by the sacrament of Confirmation, [the baptised] are more perfectly bound to the Church and are enriched with a special strength of the Holy Spirit. Hence they are, as true witnesses of Christ, more strictly obliged to spread and defend the faith by word and deed. (CC 1285)
Confirmation, it's origins
In the Old Testament the prophets announced that the Spirit of the Lord would rest on the hoped-for Messiah for his saving mission.The descent of the Holy Spirit on Jesus at his baptism by John was the sign that this was he who was to come, the Messiah, the Son of God. He was conceived of the Holy Spirit; his whole life and his whole mission are carried out in total communion with the Holy Spirit whom the Father gives him "without measure
More on Confirmation
This fullness of the Spirit was not to remain uniquely the Messiah's, but was to be communicated to the whole messianic people On several occasions Christ promised this outpouring of the Spirit, a promise which he fulfilled first on Easter Sunday and then more strikingly at Pentecost. Filled with the Holy Spirit the apostles began to proclaim "the mighty works of God," and Peter declared this outpouring of the Spirit to be the sign of the messianic age. Those who believed in the apostolic preaching and were baptised received the gift of the Holy Spirit in their turn.
