Durandus on the Liturgy of Pentecost Thursday

The Mass of Thursday in some churches does not have its own Introit, but because the Lord came down on Sunday through the sending of the Holy Spirit, and on Thursday ascended into heaven, therefore the Introit is common to Sunday and Thursday. … and thus, from Saturday to Saturday there are seven Masses, which correspond to the seven gifts of the Holy Spirit. …

Introitus Sap 1, 7 Spíritus Dómini replévit orbem terrárum, allelúja: et hoc quod cóntinet omnia, scientiam habet vocis, allelúja, allelúja, allelúja. Ps 67 Exsurgat Deus, et dissipentur inimíci ejus: et fugiant qui odérunt eum a facie ejus. Gloria Patri ... Spíritus Dómini...

Introit Wis. 1, 7 The Spirit of the Lord hath filled the world, alleluia, and that, which containeth all things, hath knowledge of the voice, alleluia, alleluia, alleluia. Ps 67 Let God arise, and let His enemies be scattered, and let those who hate Him flee from before His face. Glory be... The Spirit of the Lord...

But some churches sing the introit which is said on the following day, namely, “Let my mouth be filled with your praise.” Others have a proper Mass, namely, “God of our fathers, grant us the spirit of grace,” in which the church prays that the Holy Spirit be given to her sons for the forgiveness of sins and perform miracles. (This is actually part of the text of a troped Gloria, not an introit.) And because miracles happen through the Holy Spirit, therefore the Epistle (Acts 8, 5-8) is read in which Phillip healed many of the lame, and cast out unclean spirits, and there was great rejoicing in that city, namely, Samaria. And because all these things happen through the Holy Spirit, there follows the Gospel (Luke 9, 1-6) “Jesus called together the twelve Apostles, then gave them strength and power over all demons”, and afterwards, “take nothing on the way, neither staff nor bullet wallet”; these things can only be done by those who an abundance of the Holy Spirit.

– This Epistle also parallels that of Easter Thursday, Acts 8, 26-40, in which the same Philip (one of the seven first deacons, sometime called Philip the Evangelist to distinguish him from the Apostle) converts and baptizes the Ethiopian eunuch.

The Baptism of the Ethiopian Eunuch, ca. 1625-30, Attributed to the Flemish painters Hendrik van Balen the Elder (1575 ca. - 1632) and Jan Brueghel the Younger (1601-78). Public domain image from Wikimedia Commons.

– As an interesting aside, Durandus knew (6, 43) that the Thursdays of Lent were originally “aliturgical” days, on which Mass was not said, and that this custom was changed by Pope St Gregory II; he also understood that this history explained for some of the particularities in the arrangement of the liturgical texts of those Thursdays. However, he evidently did not realize that Pentecost Thursday has no Mass of its own for the same reason, namely, that it was originally also an aliturgical day, and also changed by St Gregory II.