Sacrament (Lat. sacramentum, the military oath or its obligation), in Christian theology, an external ordinance or rite of divine institution, significant of a supersensual grace or spiritual effect. Its earliest usage in the Old Italic version of the New Testament and in the Latin Vulgate means something sacred and hidden, and sacramentum is thus taken as an equivalent for the Greek , a secret; hence the early church fathers used the word to denote any mysterious doctrine or thing pertaining to the Christian belief or worship.
Subsequently sacramentum in the Latin church and in the Greek were restricted to certain rites or ordinances divinely instituted for imparting to the recipient an invisible grace in conformity with the visible ceremony. Both these churches believe that there are seven such sacraments, viz.: baptism, confirmation, penance, the eucharist, extreme unction, order or ordination, and matrimony. Baptism, confirmation, and order can only be received once, and are considered to impress on the soul an indelible seal or character. Baptism and penance are called "the sacraments of the dead," because ordained by Christ to restore the soul dead by sin to the life of sanctifying grace. Baptism is validly conferred on infants without the exercise of reason; but its worthy reception by the adult requires faith in the redeeming merits of Christ and compunction for past offences. The five other sacraments are called "sacraments of the living," because the first requisite condition for their worthy reception is, that the soul of the recipient should be in a state of sanctifying grace. - In the church of England many distinguished theologians, especially in recent times, have inclined to the opinion that there are in the Christian church two primary and five secondary sacraments.
The majority, however, with Protestants generally, believe in but two sacraments, baptism and the Lord's supper, on the ground that the New Testament mentions only these two as having been instituted by Christ. The "Apology" for the Lutheran confession of Augsburg mentions also penance or "absolution" as a true sacrament; but this was afterward omitted from the list of the sacraments, and confession was retained by the Lutheran churches as a mere ecclesiastical institution. The sacrament of ordination has also found advocates among modern High Lutherans. A violent controversy about what constitutes the substance of each sacrament was carried on between the Lutherans and the Reformed churches in the 16th century. As to the efficacy or operation of the sacraments, a wide difference of opinion has existed between Protestant and Roman Catholic theologians, arising in a great measure from the widely different meaning applied by the disputants to the term "faith," and to other interior dispositions required of the recipient of the sacraments. The Friends regard the rites of baptism and the Lord's supper as Jewish customs which ceased to be obligatory after the apostolic age.