It is evident from its celebration that the effect of the sacrament of Confirmation is the full outpouring of the Holy Spirit as once granted to the apostles on the day of Pentecost. From this fact, Confirmation brings an increase and deepening of baptismal grace:
– it roots us more deeply in the divine filiation which makes us cry, “Abba! Father!”;
– it unites us more firmly to Christ;
– it increases the gifts of the Holy Spirit in us;
– it renders our bond with the Church more perfect;
– it gives us a special strength of the Holy Spirit to spread and defend the faith by word and action as true witnesses of Christ, to confess the name of Christ boldly, and never to be ashamed of the Cross.

Like Baptism which it completes, Confirmation is given only once, for it too imprints on the soul an indelible spiritual mark, the “character,” which is the sign that Jesus Christ has marked a Christian with the seal of his Spirit by clothing him with power from on high so that he may be his witnesses

Catechism of the Catholic Church 1302 – 1304


​The Sacrament of Confirmation is the second of the three sacraments of Christian initiation.
 
Confirmation completes Baptism, by which in the laying on of hands and the anointing with Chrism Oil, which first happened at Baptism, we are confirmed with the fullness of the Holy Spirit.
 
We are reminded of our participation in the ministry and mission of Jesus, and strengthened to follow Jesus more closely.