The word deacon is derived from the Greek "diaconia," meaning service. In the Church today, there are two forms of diaconate: the transitional diaconate and the permanent diaconate.
The diaconate has its roots in the Church of the first century. In fact, those serving in this ministry are first recognized in Scripture, in the Acts of the Apostles. By the end of the first millennium, the diaconate had lost its permanency and was then recognized as a transitional step for men seeking ordination to the priesthood. The Council of Trent (1545 - 1563) unsuccessfully called for the restoration of the permanent diaconate. It wasn't until June 18, 1967, that Pope Paul VI implemented the Second Vatican Council's decision to reinstitute the permanent diaconate in the universal Church.
The movement to restore the permanent diaconate was well underway by the Second Vatican Council. Many reasons surfaced for bringing back this order after centuries of disuse in the Church. The Decree on the Missionary Activities of the Church reasons that "there are men who have actually been carrying out the functions of the deacons office, either by preaching the Word of God as catechist, or by presiding over scattered Christian communities in the name of the pastor or bishop."
There is a critical shortage of priests, particularly in the developing nations. In such cases, the ministry of the deacon provides liturgical and other services to Catholics who would otherwise have to do without them. The restoration can be a further source of vocations, since not all men called to ministry are attracted to the priesthood. The central reasons for the restoration are that it re-establishes the threefold ministerial hierarchy (bishops, priests, deacons) originally formulated in the early Church, and that it strengthens the diaconal ministries through sacramental grace.
The ministry of word calls the deacon to be evangelizer and teacher. Not only is he called to teach and evangelize in the traditional sense as instructor and preacher, but he takes the spirit and message of Jesus to the public arena through his generous sharing of time and talent and his concern for those around him, especially the poor. These activities engage the deacon "New Evangelization" in a most profound and meaningful way.
The ministry of liturgy calls the deacon to assist at the altar, to distribute the Eucharist especially as an ordinary minister of the Cup, to witness weddings, to preside at funerals, to administer viaticum to the sick, to lead Sunday Celebrations in the Absence of a Priest, and to preside at other rites and celebrations as appropriate. A vibrant diaconate will enhance and expand the ministry of both the presbyterate and the episcopate.
The ministry of charity and justice calls the deacon to not only serve those in need, but also to defend and act as a voice for all those who are poor, marginalized and defenseless, those who are victims, those who are ignored or despised by society. Again, to quote Pope John Paul II, "This is at the very heart of the Diaconate to which you have been called: to be servant of the mysteries of Christ and, at the same time to be servant of your brothers and sisters..." Although the deacon's service begins at the altar and returns there, "the deacons' service in the ministry of word and liturgy would be severely deficient if his exemplary witness and assistance in the Church's ministry of charity and justice did not accompany it."