EPISTLE. — This is the passage from the Letters of the Apostles or from some other book of Holy Scripture that the priest reads at Mass before the Gospel. The Church inherited the use of readings in liturgical assemblies from the Synagogue; however, while in the Synagogue the Prophets and the Law were read, in the Church were added the Letters of the Apostles, the Gospels, the Letters of the bishops, and the Acts of the martyrs.
Of the many readings in use in the early Church, only a few examples remain today, since only two are part of the current Mass: the Epistle and the Gospel. For example, the 12 prophecies of Holy Saturday and the 6 of the vigil of Pentecost are a remnant of the readings that were made during the ancient night vigil, from which then came Matins and the Mass of the Catechumens. The 5 readings of the Saturday of the Ember Days are the result of the fusion of the vigil with the Mass of the Catechumens, while on Wednesday of the Ember Days there is only one reading before that of the Epistle. In ancient times all these readings were delivered by the lector from the ambos that rose at the entrance to the presbytery, and were often declaimed with certain melodic cadences of which we still have some rare remnants today. When the celebration of Mass began to be daily and the need was felt to shorten the pontifical rite, brief selected passages from the Letters of the Apostles or from other books of Holy Scripture that had some relevance to the feast — to the mystery being celebrated — were gradually introduced.
To demonstrate then the intimate connection between the sanctifying liturgy and the laudatory liturgy, the Epistle came to be an intercalation in the Hours of the Office; so that sometimes it is not only part of the text read in the first nocturn, but, according to an ancient rule existing in Rome before St. Benedict, the Epistle is partly repeated in the chapters of the canonical Hours and in the *lectio brevis* of Prime. In general, Holy Scripture in the Epistle is cited in full and without variation. Sometimes, however, some verses are omitted — a *Fratres* is added at the beginning and a *Christo Jesu Domino nostro* (Dominica IV after Pentecost); *qui est benedictus in saecula sancti ordinum. Amen* (Dominica XVIII after Pentecost). To the Prophecies, moreover, is sometimes added: *Attende Domine omnipotens*. Some slight alteration in the text may occur for a better adaptation to the mystery being celebrated, as in the Saturday of Passion Week (Jer. 17:8).