ORCHESTRA IN LITURGICAL MUSIC. — The Church was always opposed to the use of musical instruments during sacred rites, despite the fact that in the early Middle Ages a rather bizarre symbolism attributed to instruments and their various parts subtle correspondences with the spiritual world: thus, in the seven strings of the cithara virtues vibrate, the trumpet represents the Fourth Gospel, the skin of the tympanum is mortal flesh, and the ten-stringed psaltery foreshadows the Ten Commandments. St. Thomas Aquinas declares (Sum. Theol., 2, 2, q. 91) that instruments contribute more to distracting the soul than to concentrating II.
The notable exception made for the organ is perfectly justified, on the one hand by the character of the instrument and on the other by the restrictions imposed on its practical use (v. ORGANO). Pius X’s motu proprio on sacred music (22 Nov. 1903) leaves the door open to instrumental ensembles: “In some particular cases, within due bounds and with suitable consideration, other instruments may also be admitted, but not without the special permission of the Ordinary”; and, like the organ, they must serve the singing: “simply support it and never overwhelm it” (§§ 15–16). In § 19 it prohibits the use of the piano and percussion, while in § 20 it grants that “only in some special case, with the consent of the Ordinary, may a limited, judicious selection of wind instruments, proportionate to the setting, be permitted, provided that the composition and accompaniment to be performed are written in a grave, suitable style entirely similar to that of the organ.” These directives were necessary to condemn customs handed down from the eighteenth century, since it is not “the singing with instrumental accompaniment, but the living voice that must resound in the temple: the voice of the clergy, of the singers, of the people” (apostolic constitution Divini cultus, of Pius XI, 20 Dec. 1928; AAS, 21 [1929], pp. 33 ff.). In conformity with this principle, even today in the papal chapels choral singing is never accompanied by instruments, indeed not even by the organ.
From all this it is easy to infer that the orchestra in the full sense of the term, as a large ensemble, is altogether excluded from participation in divine worship. String or wind ensembles, and therefore mixed ensembles as well, may instead be associated with the liturgy, without excluding the harp; string ensembles may also be combined with the organ, provided always that this remains within the limits of time and the elevation of style required by the dignity and spirituality of sacred art.
Edoardo Carducci Agostini