Confirmation is a Sacrament through which we receive the Holy Ghost to make us strong and perfect Christians and soldiers of Christ. 

The Third Counsel of Baltimore
Baltimore Catechism Four #166

"For 'by the sacrament of Cofirmation, [the baptized] are more perfectly bound to the Church and are enriched with a special strength of the Holy Spirit.  Hence they are, as a  true witnesses of Christ, more strictly obligated to spread and defend the faith by word and deed."   Catechism of the Catholic Church # 1285