By the Monogram of Christ is ordinarily understood the abbreviation of Christ's name formed by combining the first two letters of the Greek form (see Greek word 1, in table above) thus (see Monogram a); this monogram was also known as the Chrismon. There are, however, besides this type of monogram, two other monograms of Christ one of His name, Jesus, the other of both His names together. The most common form (that first alluded to), was adopted by Constantine the Great on his military standards. The monogram of the famous labarum, as described by Eusebius (Life of Constantine I.31), is that given above. Lactantius (How the Persecutors Died 44) describes it as "transversa X littera summo capite circumflexo", a somewhat obscure expression interpreted by Hauck ("Realencyk. für prot. Theol", s.vv. Monogramm Christi) as a X with one of its strokes perpendicular (see Monogram b) and the upper arm of this stroke rounded to form a P (see Monogram c). Many variants of these two forms exist in the monuments of the fourth and fifth centuries. The Greek letters XP combined in a monogram occur on pre-Christian coins (e.g. the Attic tetradrachma and some coins of the Ptolemies), and in some Greek manuscripts of the Christian period they are employed as an abbreviation of such words as (see Greek words 2, 3, 4). Lowrie remarks, however, that when employed as an abbreviation the X stands upright, whereas in the monogram of Christ it lies on its side (see Monogram d), thus appearing more symmetrical. The form (see Monogram c), is of Christian origin; it came into use in the course of the fourth century, and represents a stage in the development of the monogram into the cross.
The opinion of Hauck that the monogram, in the form in which it appears on the labarum, was well known in Christian society before Constantine would seem, from the circumstances of the case, to be well founded; for otherwise how would the emperor have recognized it as a Christian symbol? Yet, at the same time it must be said that it appears only rarely on pre-Constantinian monuments, and then generally as an abbreviation (compendium scriptur ) rather than as an emblem; as, for instance, in a third century inscription in the Catacomb of St. Priscilla (see Greek words 5 & Monogram a). The adoption of the monogram by Constantine for use on the imperial military standards and on the shields of the soldiers, as a symbol of Christianity, was the beginning of its popularity in the empire; During the fourth century it was represented on all manner of monuments: on public edifices, churches, sarcophagi, lamps, vestments, clothing, household utensils, etc. It appears frequently in association with inscriptions on tombs, sometimes in relation with the apocalyptic letters A and (see Greek letter 8), or with the symbolic fish, doves, palm branches, and the like. It rarely appears on Roman monuments, however, after the fatal year 410, when the Eternal City fell into the hands of Alaric, but in the East it long continued to enjoy its popularity; In the course of the fifth century, in the West, the (see Monogram c) form became the more common, but in the East the earlier form continued in favour.
A monogram formed of the initial letters of both Christ's names appears in a Roman monument of the year 268 or 279 as part of the inscription on a tomb: BENEMERENTI (in) (see Monogram e) Domi No. Two Gallic monuments with this monogram, bearing the dates 491 and 597, are noted by Le Blant, and once it occurs on an ancient lamp, in association with the apocalyptic letters A and (See Greek letter 8). In a somewhat different form it occurs in several monuments of the cemetery of St. Callistus: in these the I crosses the X horizontally instead of perpendicularly (see Monogram f). The IX monogram (for Greek words 6 the table above), also appears on some sarcophagi of Provence enclosed in a circle, thus forming a star: the star that guided the Wise Men to Bethlehem. The monogram IC XC occurs in manuscripts of the Scriptures (the Codex Alexandrinus and the Codex Claromontanus) as early as the fifth and sixth centuries. Peculiar to the Latin Church is the monogram (see Greek word 7), which occurs in the sixth century Greek-Latin Codex Claramontanus, as an abbreviation of both Our Lord's Greek names. The Greeks also employed the letters IH as an abbreviation for the name of Jesus, with a peculiar symbolic meaning. According to the Epistle of pseudo-Barnabas the circumcision by Abraham of 318 men of his household had a mystic signification. The Greek letters I E T, used as numerals, amount to 318, and at the same time the first two of these letters are abbreviations of the Name of Jesus, while the third represents the cross (Pseudo-Barnabas, c. ix). The meaning was adopted by the Greek Church, and from them it was borrowed by the Latins. The familiar monogram I H S was first popularized by St. Bernardine of Siena in the early fifteenth century and later, with the addition of a cross over the central letter, by the Society of Jesus. (See article I.H.S.).
TYRWHITT in Dict. Christ. Antiq. (London, 1875-80), s.v. Monogram; LOWRIE, Monuments of the Early Church (New York, 1901); PIPER HAUCK in Realencyk. f. prot. Theol., s. vv. Monogramm Christi (Leipzig. 1903); KRAUS in Real-encyklopädie der christlichen Alterthümer s.v. (Freiburg, 1886).
APA citation. (1911). Monogram of Christ. In The Catholic Encyclopedia. New York: Robert Appleton Company. http://www.newadvent.org/cathen/10488a.htm
MLA citation. "Monogram of Christ." The Catholic Encyclopedia. Vol. 10. New York: Robert Appleton Company, 1911. <http://www.newadvent.org/cathen/10488a.htm>.
Transcription. This article was transcribed for New Advent by Douglas J. Potter. Dedicated to the Sacred Heart of Jesus Christ.
Ecclesiastical approbation. Nihil Obstat. October 1, 1911. Remy Lafort, S.T.D., Censor. Imprimatur. +John Cardinal Farley, Archbishop of New York.
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