The sacrament of Confirmation is a sacrament that seals the process of Christian initiation to the Church. It is a sacrament necessary for someone to qualify to be a baptismal or Confirmation sponsor because it makes them a full member of the the Church with all the graces accompanying it.

The Catechism of the Catholic Church lists five effects of Confirmation:
1) It roots us more deeply in our Faith 
2) It unites us more firmly to Christ;
3) It increases the gifts of the Holy Spirit in us;
4) It renders our bond with the Church more perfect 
5) 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