Chapter 21 — Part II: The Sacraments — Holy Orders
Section 44. Now the subdiaconate is the first degree of (major orders). Its function, as the name itself indicates, is to serve the deacon at the altar. It is the subdeacon who should prepare the altar linen, the vessels and the bread and wine necessary for the celebration of the Holy Sacrifice. He also it is who presents water to the Bishop or priest when he washes his hands during the Sacrifice of the Mass. It is also the subdeacon who now reads the Epistle which in former times was read at Mass by the deacon. He assists as witness at the Holy Sacrifice, and guards the celebrant from being disturbed by anyone during the sacred ceremonies.