Conditional baptism

Mainline Christian theology (including Roman Catholic, Eastern Orthodox, Oriental Orthodox, Church of the East, Anglican, Lutheran and most other Protestants) has traditionally held that only one baptism is valid to confer the benefits of this sacrament. In particular, the Council of Trent defined a dogma that it is forbidden to baptize a person who is already baptized, because the first baptism would make an indelible mark on the soul. Therefore, in cases where the validity of a baptism is in doubt, a "conditional" baptism may be performed.

Such uncertainty may result from questions about whether the Triune name of God was used by the person administering the baptism. In some cases, there are doubts about whether a church from which someone is converting baptizes in a valid manner. For example, the Catholic Church has said that the validity of baptisms in the The Church of Jesus Christ of Latter-day Saints (which does not practice conditional baptism) and in some other communions is doubtful. Another example of a case requiring conditional baptism is when an emergency baptism has been performed using impure water. Then, the validity of the baptism is in question. In that case, a conditional baptism is later performed by an ordinary minister of the sacrament with certainly valid matter.

In a typical baptism, the minister of the sacrament (in the Catholic Church usually a deacon or a priest, but sometimes, especially when the baptized is in imminent danger of death, a lay person or even a non-Christian) says

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