Canon XLIII.
Canons of Local Councils Received Ecumenically (Ancyra, Gangra, Neocaesarea, Antioch, Laodicea) · The Seven Holy Ecumenical Councils
On this canon the commentators find nothing to say in addition to their remarks on Canons xxj., and xxij., except that the “prayer” is not their own private prayer, but the prayer of the Liturgy. It has struck me that possibly when there was no deacon to sing the litany outside the Holy Gates while the priest was going on with the holy action within, subdeacons may have left their places at the doors, assumed the deacon’s stole and done his part of the office, and that it was to prevent this abuse that this canon was enacted, the “prayer” being the litany. But as this is purely my own suggestion it is probably valueless.
LocalE 5.50.6