From the beginning in the Church, God called certain men from the community to be consecrated for preaching the Gospel, administering the sacraments and caring for the needs of the community--some for service as bishops, others as priests and some for service as deacons. We know what a bishop or a priest does because their ministry is very familiar to every Catholic. It is a different case with deacons, however, since the diaconate as a permanent state of life was not in existence in the West from the fourth century until after the Second Vatican Council.
In 1968, when the American bishops asked the Pope to authorize the restoration of the Permanent Diaconate in our country, they pointed to five reasons, two of which were -"to complete the hierarchy of sacred orders and to enrich and strengthen the various diaconal ministries at work in the U.S. with the sacramental grace of the diaconate." "To complete the hierarchy of sacred orders" refers to the fact that the diaconate is an integral part of the Church's three-fold ordained ministry (bishop, priest, and deacon). The bishops have emphasized that the diaconate and the priesthood, especially, are complementary ministries. "The diaconate is not an abridged form of the priesthood, but a full order in its own right" and for the good of the Church as a whole "the two ministries must be exercised in communion with one another."5 (National Directory for the Formation, Ministry, and Life of Permanent Deacons in the United States)
To understand diaconal ministry it is essential to see deacons in the context of the three general areas of service to which they are especially called: the ministry of the Word, ministry of the liturgy, and ministry of charity and justice. Everything a deacon does falls within this framework.
Deacons participate in sacred orders, and just as bishops and priests, they receive the sacrament of Holy Orders. As a result of this ordination, they are empowered to preach, baptize, assist at the Eucharist, and witness marriages. However, as with bishops and priests, deacons do so much more than this. Deacons are not only ordained to attend to the religious needs of people; they are specially ordained to attend to their human needs. This was very true in the early days of the Church. We read in the Acts of the Apostles that deacons are ordained to care for widows and orphans. Today the deacon is called forth from the community and ordained a public minister of the Church because he is a man of faith who is capable and willing to express care and concern for his brothers and sisters. Social justice action on behalf of the alienated and oppressed is a key element of diaconal ministry.
In the final analysis, however, permanent deacons should be understood not in terms of what they do but who they are - servants. Although deacons are involved in some way in the three general areas mentioned, their specific activities can vary so much that a detailed description applicable to all isn't possible. However much an individual deacon's ministry may vary, the basic elements are always present: the invitation of the Spirit, public expression of and response to this call through ordination; sharing in accountability for the realization on earth of God's Kingdom; acceptance by the community they are called to serve, and complete self commitment to humbly service in Christ's name and in the name of the Church.