CATECHISM OF THE CATHOLIC CHURCH
SECOND EDITION

Paragraphs 1294–1297

1294 Anointing with oil has all these meanings in the sacramental life. The pre-baptismal anointing with the oil of catechumens signifies cleansing and strengthening; the anointing of the sick expresses healing and comfort. The post-baptismal anointing with sacred chrism in Confirmation and ordination is the sign of consecration. By Confirmation Christians, that is, those who are anointed, share more completely in the mission of Jesus Christ and the fullness of the Holy Spirit with which he is filled, so that their lives may give off "the aroma of Christ."
1295 By this anointing the confirmand receives the "mark," the seal of the Holy Spirit. A seal is a symbol of a person, a sign of personal authority, or ownership of an object. Hence soldiers were marked with their leader's seal and slaves with their master's. A seal authenticates a juridical act or document and occasionally makes it secret.
1296 Christ himself declared that he was marked with his Father's seal. Christians are also marked with a seal: "It is God who establishes us with you in Christ and has commissioned us; he has put his seal on us and given us his Spirit in our hearts as a guarantee." This seal of the Holy Spirit marks our total belonging to Christ, our enrollment in his service for ever, as well as the promise of divine protection in the great eschatological trial.
1297 The consecration of the sacred chrism is an important action that precedes the celebration of Confirmation, but is in a certain way a part of it. It is the bishop who, in the course of the Chrism Mass of Holy Thursday, consecrates the sacred chrism for his whole diocese. In some Eastern Churches this consecration is even reserved to the patriarch:

The liturgy of Antioch expresses the epiclesis for the consecration of the sacred chrism (myron) in this way: "[Father . . . send your Holy Spirit] on us and on this oil which is before us and consecrate it, so that it may be for all who are anointed and marked with it holy myron, priestly myron, royal myron, anointing with gladness, clothing with light, a cloak of salvation, a spiritual gift, the sanctification of souls and bodies, imperishable happiness, the indelible seal, a buckler of faith, and a fearsome helmet against all the works of the adversary."