Baptism and the Church
Out of God's revealed word, the Church has developed a theology of baptism that takes into account the lived experience of the Church throughout its history, its liturgical life and its theological developments.
The notion of baptism as a sacrament dates back to the early centuries of Christianity. The word "sacrament" is borrowed from the Latin, sacramentum, which in Roman times referred to an initiation rite in which soldiers promised their fidelity to their commander. In teaching Gentiles, the Church used the word sacramentum to explain the rite of Christian initiation in which the converts would commit themselves to the service of God. When Christianity supplanted polytheism in the empire, the Roman sense was dropped, and the word was expanded to any symbol that represented one's relationship to God.
By the fifth century, St. Augustine referred to a sacramentum as anything that was "a sign of a sacred reality." By the twelfth century, the word was restricted to those rituals of the Church of which Baptism and Eucharist are primary.
The Church's baptismal tradition has shaped the rite as we know it in the Church today. From the Church's expression of corporate faith in the early Church, through conversion and a ritual that was aimed at sustaining one in the faith in the face of persecution and death, to its present ritual form, baptism continues to unite the baptized individual with Christ and his body, the Church.
Baptism: A lifelong journey