A
Aramis
Guest
In the Old roles…I think it’s a bad idea for clerics of one order to function as though of another - & I can’t see the point of subdeacons, at all.
The Bishop was the celebrant. The person in alter Christus and in loco Christus.
The priests assisted the Bishop.
They are the ordinary ministers of the Body of Christ
The priests could be assigned to be celebrant in remote parishes in loco episcopus. The priests taught the faith. The priests heard confessions in loco episcopus.
The Deacons assisted the priests, and lead the litanies. The deacons read the Gospels, and might read a prepared homily. He is the ordinary minister of the Blood in the early church (and again, now, in the modern Roman use). He is the lowest order who may intinct the body into the blood.
The Subdeacon holds the gospel for the deacon, AND reads the epistle. He supervises the Cantors and Acolytes. He teaches the Lectors how to read in psalm-tone and lection tone. He holds the patton with the Body if the priest needs both hands while distributing communion. He holds the Cup if the deacon is intincting. He may be used as the third Minister of Holy Communion if need be.
The Lector holds the epistle book for the Subdeacon. He is learning how to chant the Lection. He is vested the same as an acolyte.
The Acolytes assist the subdeacon in assisting the deacon and priest. If the Subdeacon is already serving as Extraordinary Minister of Holy Communion, or none is present, the Acolyte may be used as one. Until recently, this was in fact the lowest order allowed to do so during the liturgy.
The Cantor (At some times a minor order) leads the Alleluia, Gradual, and Hymns, and public sung responses.
In the Modern, Pauline, Ordinary Form, the subdeacon has no real role; if one is present, he is obliged to offer to chant or read the epistle, and to serve as acolyte. He may, as an instituted acolyte as well, purify the vessels after communion. He is the proper Extraordinary Minister of Holy Communion.
An instituted acolyte is also obliged to serve as an alter server, and as an EMHC, before any other non-subdeacon layman.
An instituted lector is to read in place of any lay reader assigned when present. It is in fact their duty.