Christogram

A Christogram (Latin: Monogramma Christi)[a] is a monogram or combination of letters that forms an abbreviation for the name of Jesus Christ, traditionally used as a religious symbol within the Christian Church.

The name Jesus, spelt ΙΗΣΟΥΣ in Greek capitals, has the abbreviations IHS (also written JHS, IHC, or ΙΗΣ).

[2] In antiquity, the cross, i.e. the instrument of Christ's crucifixion (crux, stauros), was taken to be T-shaped, while the X-shape ("chiasmus") had different connotations.

This entire compound divided lengthways into two parts, which he joined to one another at the centre like the letter X, and bent them into a circular form, connecting them with themselves and each other at the point opposite to their original meeting-point; and, comprehending them in a uniform revolution upon the same axis, he made the one the outer and the other the inner circle.The two great circles of the heavens, the equator and the ecliptic, which, by intersecting each other form a sort of recumbent chi and about which the whole dome of the starry heavens swings in a wondrous rhythm, became for the Christian eye a heavenly cross.Justin Martyr in the 2nd century makes explicit reference to Plato's image in Timaeus in terms of a prefiguration of the Holy Cross.

[5] An early statement may be the phrase in Didache, "sign of extension in heaven" (sēmeion epektaseōs en ouranōi).

[6] The most commonly encountered Christogram in English-speaking countries in modern times is the Χ (or more accurately, Chi), representing the first letter of the word Christ, in such abbreviations as Xmas (for "Christmas") and Xian or Xtian (for "Christian").

Because the chrismon was used as a kind of "invocation" at the beginning of documents of the Merovingian period, the term also came to be used of the "cross-signatures" in early medieval charters.

In the Latin-speaking Christianity of medieval Western Europe (and so among Catholics and many Protestants today), the most common Christogram became "IHS" or "IHC", denoting the first three letters of the Greek name of Jesus, ΙΗΣΟΥΣ, iota-eta-sigma, or ΙΗΣ.

The IHS monogram with the H surmounted by a cross above three nails and surrounded by a Sun is the emblem of the Jesuits, according to tradition introduced by Ignatius of Loyola in 1541.