Baptism of a ChildYou and I are Anointed by the Holy Spirit when we receive the Sacraments of Baptism and Confirmation. With these sacraments we receive an anointing on our forehead with Sacred Chrism. This is a physical sign that we have received the Holy Spirit. By the Sacraments of Baptism and Confirmation, Christians — the anointed ones — share more fully in the mission of Jesus and in the fullness of the Spirit with whom He is filled.

When we are confirmed, we receive a spiritual mark or seal of the Holy Spirit. Jesus was sealed by the Father.  St. Paul writes:

“It is God who establishes us with you in Christ, and has commissioned us; he has put his seal upon us and given us his Spirit in our hearts as a guarantee.”
— New American Bible: Revised Edition (NABRE), 2011, 2 Corinthians 1:21–22

The Catechism provides the following:

“This seal of the Holy Spirit marks our total belonging to Christ, our enrollment in his service forever, as well as the promise of divine protection.”
— Catechism of the Catholic Church (CCC), 2000, para. 1296