This post is mostly a translation of notes by our long-time contributor and Ambrosian Rite expert, Nicola de’ Grandi.
In the Ambrosian Rite, Advent begins on the Sunday after the feast of St Martin on November 11th. This means that in a year such as this one, in which Christmas Eve falls on Sunday, the Ambrosian Advent is at its longest, six full weeks and one day, whereas the Roman Advent is at its shortest, three weeks and one day. Today is therefore the Sixth Sunday of Advent in Milan, whereas in Rome it is only the third. All Ambrosian sources, going back to the very earliest, attest to the character of this day as a feast of the Virgin Mary; it is therefore also subtitled in the modern editions of the liturgical books, “the Solemnity of the Incarnation.”
A reconstruction of the cathedral complex of Milan, with the summer church of St Thecla on the left, and the winter church of the Virgin Mary at the right. The octagonal structure in front of St Thecla is the baptistery of St John; the smaller structural beneath it is the baptistery of St Stephen. At the lower right is a partial reconstruction of the interior of the baptistery of St John.
The Duomo of Milan as it stands today is the result of a project which began in 1386, to replace the two cathedrals which had hitherto served the see of St Ambrose. The “winter church”, as it is still named in Ambrosian liturgical books, was the smaller of the two, dedicated to the Virgin Mary, and used from the Third Sunday of October, the feast of its dedication, until Holy Saturday; it stood where the modern cathedral stands, but was nowhere near as large. The larger “summer church” stood on the opposite end of the modern Piazza del Duomo, and was dedicated to St Thecla, for which reason her name is included in the Canon of the Ambrosian Mass. In the Ambrosian Rite, several liturgical days (the vigil of Easter and its whole octave, the vigil and feast of Pentecost, and the Sixth Sunday of Advent) have two Masses assigned to them, one of which was originally celebrated in the summer church, and the other in the winter church. Ever since the two buildings were consolidated into a single, massive church, one of these two has been celebrated in a side-chapel. (The ancient complex also had two baptisteries, one dedicated to the Baptist, and known as St John “ad fontes”, and the other to St Stephen.)
The first chant of the Ambrosian Mass is called the Ingressa, and is analogous to the Roman Introit, but has no psalm verse, doxology or repetition. At the Mass of the Incarnation, the text is a loose translation of a hymn originally composed for Vespers of the Nativity of St John the Baptist in the Byzantine Rite.
Ingressa Videsne Elisabeth cum Dei Genitrice Maria disputantem: Quid ad me venisti, mater Domini mei? Si enim scirem, in tuum venirem occursum. Tu enim Regnatorem portas, et ego prophetam: tu legem dantem, et ego legem accipientem: tu Verbum, et ego vocem proclamantis adventum Salvatoris.
Dost thou see Elizabeth discussing with Mary, the Mother of God: Why hast Thou come to me, o mother of my Lord? For if I had known, I would have come to meet Thee. For thou bearest Him that reigneth, and I the prophet; Thou the Giver of the Law, and I him that receiveth it; Thou the Word, and I the voice of him that proclaimeth the coming of the Savior.
The Gospel of this Mass is that of the Annunciation, Luke 1, 26-38, whereas the Mass of Advent on the same day is of the Visitation, verses 39-46. Here we see a fresco in which both episodes are depicted, from the church of Santa Maria foris portas (outside the gates) at Castelseprio, about 28 miles to the northwest of Milan, painted in the 9th century.
Ambrosian Missals indicate that the station for the Mass of the Sixth Sunday of Advent is “in the winter church”, while that of the Incarnation is “at the church of St Mary”, even though the winter church of the Duomo complex is St Mary. In point of fact, this refers to a different church, “Sancta Maria ad Circulum”, which was built on top of the curved side of the ancient Roman chariot racing circus in Milan, but destroyed in 1789. After celebrating the first Mass, the archbishop and various other members of the clergy would proceed to the station, and attend the second one. (Similar processions to the churches of the more important Saints were formerly held on their feast days.)
The Mass of the Incarnation, with the station noted ‘ad Sanctam Mariam’, in an Ambrosian Missal printed in 1594.
The following recording includes several of the antiphons which were sung during the procession, many of which are also sung in the Divine Office of the day.