Canonical digits

Canonical digits, also referred to as liturgical digits, are a posture or bodily attitude of prayer used during the celebration of the rite of the Holy Mass. This gesture is performed by any Catholic priest after consecration and before ablutions, standing and joining his thumb and index finger in a circle, and holding the other fingers straight away from the palm.

Canonical digits are used during the rite of the Holy Mass by joining thumb and index in both hands separately while holding the remaining three fingers straight up.

During the lavabo, the priest washes the ends of the thumbs and index fingers, then wipes them with the manuterge. As he begins the rite of consecration, the priest wipes the thumb and index of each hand making a sign of the cross on the corporal saying "qui pridie quam pateretur" (at the time he was betrayed). From this moment of consecration to the ablution after communion, the priest does not separate the thumb and index finger in order to avoid any particles of the host from falling.

When the priest must hold the chalice with one hand, he takes it by the knot. When he holds it with both hands, he takes it, as a general rule, with the right hand by the knot, and with the left by the foot. Before the consecration and after the ablution, he places his thumb in front of the knot, and all the other fingers behind.

The practise of canonical digits is not found among the Eastern churches and little evidence is available to prove this practise before the East–West Schism in 1054. In fact, iconographic witnesses would suggest the practise was not universal even in the West during the first millennium. Thus for example, it can be observed on a fresco in the lower church of San Clemente al Laterano in Rome that a priest at the altar at the end of the canon does not hold his finger and index with this caution. A new practise evolved in the 11th century. According to the Cluniac Customary, written about 1068 by the monk Bernhard, the priest at the consecration should hold the host quattuor primis digitis ad hoc ipsum ablutis (with the four first fingers previously rinsed)." After the consecration, even when praying with outstretched arms, some priests began to hold those fingers which had "touched" the Lord's Body, pressed together, others even began this at the ablution of the fingers at the offertory. In one form or another the idea soon became a general rule. The practise was criticized c. 1085 by Bernold of Constance in his Micrologus de ecclesiasticis observationibus.

In the 13th century, for French liturgist Guillaume Durand, thumb and forefinger may be parted after the consecration only quando oportet hostiam tangi vel signa fieri, which means that the fingers can be disjoined when making the sign of the cross. Similar provisions were made in the Ordo of Giacomo Gaetani Stefaneschi in 1311, in the Liber ordinarius of Liege as well as in the Dominican sources of the same, dated about 1256, all insisting that the liturgical digits be kept after the Lavabo.

In the Supplementum of the Summa Theologica, the disciples of Thomas Aquinas explain the rationale for this "gesture of Franco-Roman piety signifying the dispositions of the religious soul" answering an objection against those who objected unncessary "gesticulations": "the thumb and first finger, after the consecration, because, with them, he had touched the consecrated body of Christ; so that if any particle cling to the fingers, it may not be scattered: and this belongs to the reverence for this sacrament."

The practise was made into a universal rubric by the Roman Missal promulgated by the Council of Trent which ended in 1563 insisting on the belief in the real presence in every particle of the Eucharist, in reply to doubts spread by the Protestant Reformation: "If anyone deny that Jesus Christ is contained whole and entire under each species in the adorable sacrament of the Eucharist, and also under each particle of these species, after they are divided, let him be anathema". The Roman Missal made the practise of liturgical digits somewhat more strict: even the signa no longer formed an exception, the fingers simply remain closed: semper faciat si aliquod fragmentum digitis adhæreat, which was confirmed until the 1962 edition of the Roman Missal by Pope John XXIII.