In Christian denominations that practice infant baptism, confirmation is seen as the sealing of the covenant created in baptism. Those being confirmed are known as confirmands. For adults, it is an affirmation of belief. It involves laying on of hands.

Catholicism views confirmation as a sacrament. The sacrament is called chrismation in the Eastern Christianity. In the East it is conferred immediately after baptism. In Western Christianity, confirmation is ordinarily administered when a child reaches the age of reason or early adolescence. When an adult is baptized, the sacrament is conferred immediately after baptism in the same ceremony. Among those Christians who practice teen-aged confirmation, the practice may be perceived, secondarily, as a "coming of age" rite.

In many Protestant denominations, such as the Anglican, Lutheran, Methodist and Reformed traditions, confirmation is a rite that often includes a profession of faith by an already baptized person. Confirmation is required by Lutherans, Anglicans and other traditional Protestant denominations for full membership in the respective church. In Catholic theology, by contrast, it is the sacrament of baptism that confers membership, while "reception of the sacrament of Confirmation is necessary for the completion of baptismal grace". The Catholic and Methodist denominations teach that in confirmation, the Holy Spirit strengthens a baptized individual for their faith journey.

Confirmation is not practiced in Baptist, Anabaptist and other groups that teach believer's baptism. Thus, the sacrament or rite of confirmation is administered to those being received from those aforementioned groups, in addition to those converts from non-Christian religions. The Church of Jesus Christ of Latter-day Saints does not practice infant baptism, but individuals can be baptized after they reach the "age of accountability". Confirmation in the LDS Church occurs shortly following baptism, which is not considered complete or fully efficacious until confirmation is received.

There is an analogous ceremony also called confirmation in Reform Judaism.