The Hebrew Scriptures tell the story of God’s saving action on behalf of God’s people. God bound Himself to a covenant to save His people. With Christ, a new covenant of the kingdom of God dawned. Christians were those who believed that the covenant promises of God were now being fulfilled in the mystery of Christ. Christ was the new oath, the new covenant. Hebrew religious rituals, in a similar manner as Hebrew theology, were transformed into Christian rituals or sacred actions.
The term sacred action refers to the relation established between the activity of Christ and the baptized community in its celebration of the of the sacraments. Even during Jesus’ public ministry, His disciples were becoming aware that He was bringing into being a new order of things, a new breaking into human history of the kingdom of God. He was providing a new perspective on God, His Father, and pointing to a new way of relating to God. However, only with the Easter experience after Jesus’ crucifixion, which made the disciples aware that Jesus was still humanly alive and mysteriously present to them in His Spirit, did they slowly grasp the profound transformation of life’s meaning that had occurred.
Gathering together, especially for communal meals, these first Christians shared with one another their recollections of Jesus’ life and death and their awareness of this enduring Christ-mystery which had changed their lives. Slowly, they developed certain rituals to celebrate the new divine-human covenant established by Jesus’ death and resurrection. In particular, they gave a special form to the practice of baptizing people and used it to initiate into the community those who accepted the gospel message. They celebrated some special meals, which quickly developed into the breaking of the bread, the Christian Communion. Though Jesus himself did not leave these rituals as such to his followers, it was His life, and particularly His death and resurrection, that “instituted these sacramental rituals” by being the mystery the rituals celebrate.
Early Christians, then, lived and prayed with the awareness of sharing in “the great mystery revealed in Christ,” the mystery of God’s saving presence in the lives of people. This was, in the full sense of the term, a new life; actually, it was the beginning of that unending life which Jesus had promised to those who would receive Him as sent from His Father. Through the ritual of Christian initiation one entered into this new Spirit-life that came from Jesus’ own passage into Spirit-filled risen life. As Paul explained in his letter to the Christians at Rome, in baptism one enters somehow into the death and resurrection of Christ and possesses the Spirit as the creative source of unending life.
It was this great mystery that was celebrated in the breaking of the bread. Without yet reflecting on the way in which it gave grace, the early decades—indeed the early centuries—believed that the shared bread and wine which became the body and blood of the risen Lord was a continuing food for the new life that had begun with baptism. At the same time, they were aware that in “proclaiming the death of the Lord until he comes in glory,” they were professing together their Christian faith. They were stating their acceptance of the preached gospel, but more than that, they were pledging themselves to faithful living out of their Christianity. So, the Latin word sacramentum (which means “an oath, a solemn promise”), along with the earlier Greek word mysterion, were applied to these rituals, as well as to other Christian rituals such as ordination or reconciliation which emerged in the life of the church.