In case of urgent need, anyone who knows and wills to do so may administer this sacrament. Even an unbeliever can bestow true Baptism if he performs the rite correctly and has the intention of doing what Christ or his Church wants done by Baptism. The rite itself is easy to perform. For Catholics, the minister of Baptism under ordinary conditions is the parish priest or deacon. Before adults are baptized, they must have some understanding of the truths of the Catholic Faith, and freely profess a true faith in such truths.
Baptism demands an inner conversion in any adult who receives it.
The repentance St. Peter spoke about involves a change of mind and heart, an inward desire to be purified from sin. Moreover, the baptized person must be prepared to lead a new life inspired by grace. A willingness to be baptized, repentance, and faith are, then, the dispositions adults must have to receive the sacrament of Baptism. The Church insists that infants be baptized as soon as possible, which is understood to mean at least within a month after birth. The practice of baptizing infants goes back to apostolic times.