Baptism Ceremony

The Baptism ceremony is made up of a select group of seven bishops, and Archbishop Jio.

It is a ceremony where the willing receive the sacred sign on their forehead. It only happens within the Barsburg Church once every year, and is mainly performed on children who are younger than 15 years old so they will not be violated by the Kor.

The ceremony is considered a very important event as all selected Bishops are expected to attend, with those absent having to have very good reasons.

Purpose
The purpose of the Baptism is to help those who have received it fight against the temptation of a Kor by purifying their souls, and, as with a normal baptism, it is done with holy water being applied to the person's forehead. However, a strange claw-like device is used to do so.

It appears that those who have been baptised are completely protected against Kor, as in the manga a man said the One-winged Kor Soldier became a Kor because he had not received God's protection. However, those whose souls are already tainted, by actions like murder, will still be unprotected even after baptism,  though this rule may not apply to those with beautiful souls, such as Teito and Ouka.

Relation to real-world Christianity
The method and technique of baptism used, pouring as opposed to submersion or immersion, are most closely related to Lutheranism, a branch of western Christianity. The beliefs shown in-universe, that the baptism will help protect against temptation are also shared by Lutherans.

"Baptism is a miraculous Sacrament through which God creates and/or strengthens the gift of faith in a person's heart."

- Lutherian belief on baptism