From the The Catholic Encyclopedia
IHS
A monogram of the
name of Jesus Christ. From the third century the names of our Saviour are sometimes shortened, particularly in
Christian inscriptions (IH and XP, for Jesus and Christus). In the next century the “sigla” (
chi-rho) occurs not only as an abbreviation but also as a symbol. From the beginning, however, in
Christian inscriptions the
nomina sacra, or
names of Jesus Christ, were shortened by contraction, thus IC and XC or IHS and XPS for
Iesous Christos. These Greek monograms continued to be used in Latin during the
Middle Ages. Eventually the right meaning was lost, and erroneous interpretation of IHS led to the faulty orthography “Jhesus”. In Latin the learned abbreviation IHC rarely occurs after the Carlovingian era. The mongram became more popular after the twelfth century when St. Bernard insisted much on devotion to the
Holy Name of Jesus, and the fourteenth, when the founder of the Jesuati, Blessed John Colombini (d. 1367), usually wore it on his breast. Towards the close of the
Middle Ages IHS became a symbol, quite like the
chi-rho in the Constantinian period. Sometimes above the H appears a cross and underneath three nails, while the whole figure is surrounded by rays. IHS became the accepted iconographical characteristic of St. Vincent Ferrer (d. 1419) and of St. Bernardine of Siena (d. 1444). The latter holy missionary, at the end of his sermons, was wont to exhibit this monogram devoutly to his audience, for which some blamed him; he was even called before Martin V. St. Ignatius of Loyola adopted the monogram in his seal as general of the
Society of Jesus (1541), and thus it became the emblem of his institute. IHS was sometimes wrongly understood as “Jesus Hominum (or Hierosolymae) Salvator”, i.e.
Jesus, the Saviour of men (or of Jerusalem=Hierosolyma).
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