Ordinary Ministers of Holy Communion are bishops, priests, and deacons. These persons distribute Holy Communion by virtue of their ordination. "It is first of all the office of the priest and the deacon to minister Holy Communion to the faithful who ask to receive it. It is most fitting, therefore, that they give a suitable part of their time to this ministry of their order, depending on the needs of the faithful" (Holy Communion and Worship of the Eucharist Outside Mass, 17).
Under certain circumstances, members of the faithful may be delegated to distribute Holy Communion by a bishop (or a priest, on a single occasion). These persons are known as Extraordinary Ministers of Holy Communion. Instituted acolytes (usually seminarians and candidates for the permanent diaconate) become Extraordinary Ministers through their institution. The role of an Extraordinary Minister of Holy Communion does not replace that of an Ordinary Minister, but supplements it on a provisional basis (Redemptionis Sacramentum, 151). When a sufficient number of Ordinary Ministers is present for the distribution of Holy Communion, Extraordinary Ministers of Holy Communion should not serve.
The term "Minister of the Eucharist" refers to those who confect the Sacrament of the Eucharist in persona Christi (Redemptionis Sacramentum, 154; CIC, 900). As such, it applies only to bishops and priests.
Determination of the need for Extraordinary Ministers of Holy Communion should be made by the pastor of a parish. Two areas of need should be considered:
a. That of facilitating distribution of Holy Communion at Mass on Sundays and weekdays so that the Communion rite does not become unduly prolonged; and
b. That of providing Holy Communion on a regular basis, especially from Sunday Mass, for the sick and those confined to their homes or institutions within the parish.
The Instruction Redemptionis Sacramentum states that Extraordinary Ministers of Holy Communion may be used during Mass when a "priest and deacon are lacking, when the priest is prevented by weakness or advanced age or some other genuine reason, or when the number of faithful coming to Communion is so great that the very celebration of Mass would be unduly prolonged" (158). In these cases, it is appropriate for Extraordinary Ministers of Holy Communion to serve. Extraordinary Ministers of Holy Communion should not serve when there will otherwise be only a brief prolongation of the Mass (Redemptionis Sacramentum, 158).
Extraordinary Ministers of Holy Communion may be asked to assist in the distribution of the Precious Blood. When this takes place, "their number should not be increased beyond what is required for the orderly and reverent distribution of the Body and Blood of the Lord" (Norms for the Distribution and Reception of Holy Communion Under Both Kinds in the Dioceses of the United States of America, 28). The bishops of the United States also note that, "in practice, the need to avoid obscuring the role of the priest and the deacon as the Ordinary Ministers of Holy Communion by an excessive use of Extraordinary Ministers might in some circumstances constitute a reason either for limiting the distribution of Holy Communion under both species or for using intinction instead of distributing the Precious Blood from the chalice" (Norms, 24).
The Pastoral Care of the Sick directs pastors to provide for the frequent reception of Holy Communion by the sick and aged (72). These individuals have the right to periodic visits by priests, who, in addition to bringing Holy Communion, can offer the Sacraments of Penance and Anointing of the Sick, bringing added comfort and spiritual assistance.
Extraordinary Ministers of Holy Communion may be asked to assist the priests and deacons of a parish in their service to the sick and homebound. This need for Extraordinary Ministers of Holy Communion can arise when distance "makes it difficult to bring Communion, especially as Viaticum to the sick in danger of death; or when the sheer number of sick people, especially in hospitals or similar institutions, requires several ministers" (Immensae Caritatis, I).
It is particularly appropriate that Holy Communion be brought to the sick from Sunday Mass (see Pastoral Care of the Sick, 73). Sunday, however, is a day on which the pastoral ministry of priests and deacons can make it difficult for them to bring Holy Communion to the sick at home or in healthcare facilities. Extraordinary Ministers of Holy Communion may serve in these circumstances as well.