A sacrament is recognized by the church to be genuine and true when certain minimum requirements are met. These requirements concern proper form, matter, minister, and intent. The form means the words of prayer that are used in the sacramental rite, and the matter concerns the material or gesture constituting the outward and visible sign of a sacrament. The matter in baptism is water; bread and wine are the matter in the eucharist. The minister must be properly qualified and intend to do what the church intends in celebrating the sacrament. The minister at the eucharist is the celebrant, who must be a bishop or priest. The minimum form for a valid sacrament does not require the entire BCP liturgy. For example, an emergency baptism may be administered according to the form, “I baptize you in the Name of the Father, and of the Son, and of the Holy Spirit” (BCP, p. 313). In the situation of an emergency baptism, any baptized person can be a qualified minister of the sacrament. This minister would need to baptize with water, and intend to do what the church does in baptism. The concept of sacramental validity dates from the third century, when the Church of Rome held that schismatics and heretics could administer valid baptism. This contradicted the position of Cyprian, Bishop of Carthage, that the church's sacraments could not be administered by anyone outside the church. Augustine of Hippo subsequently insisted in his controversy with Donatism that the personal unworthiness of the minister does not impair the validity of sacraments celebrated by the minister (see Art. XXVI, Articles of Religion, BCP, p. 873). See Augustine of Hippo.
Glossary definitions provided courtesy of Church Publishing Incorporated, New York, NY,(All Rights reserved) from “An Episcopal Dictionary of the Church, A User Friendly Reference for Episcopalians,” Don S. Armentrout and Robert Boak Slocum, editors.