Nomina sacra is Latin for “sacred name.” In many old Christian manuscripts, the names God, Christ, Jesus, and Lord are abbreviated with the first and last letter of each word (although there can be some variation), with an overbar across the top of both letters indicating a contraction or abbreviation. This abbreviation in an early Christian manuscript is referred to as nomina sacra or sometimes nomina divina (“divine name”).
For example, the symbol ΘC is a nomina sacra, being an abbreviated form of the Greek word for “God,” ΘεOC. To some extent, the use of these abbreviations is specific to the scribe, and not every manuscript follows the same practices all the time. But the use of nomina sacra is prevalent enough among extant manuscripts to recognize the trend.
Generally speaking, the practice seems to have been a sign of honor or special respect for the name being abbreviated or contracted. Most ancient Jews were hesitant to speak or write the name of God lest they inadvertently use His name in vain. For instance, the Hebrew name Yahweh was so sacred that it was never pronounced. In fact, we don’t even know for sure how it was pronounced because we only have the consonants YHWH. The vowels a and e in YaHWeH have been supplied by later scholars based on the best evidence for the pronunciation. The Hebrew text Old Testament was originally written with only consonants. Native speakers would have understood how to pronounce the words without vowels, especially since most Hebrew words have a regular consonant-vowel-consonant construction. Unlike English, it is rare for two or more vowels to be found together in Hebrew, and two consonants are usually only found together if they are in separate syllables. (Nglsh spkrs cn stll rd txts wth nly cnsnnts bt wth sm dffclty.) Later, vowels were added to Hebrew manuscripts to preserve the pronunciation for generations to come and to facilitate easier reading for those not as familiar with the language.
When God’s name, YHWH, had vowels added, the vowels were taken from the word Adonai (“Lord”), and the word was always pronounced Adonai. (This is reflected in the KJV by the translation “LORD” in all capital letters wherever the Hebrew has YHWH.) Today, many Jews who are religiously observant will not write the word God but instead will write G-d for much the same reason. The nomina sacra in many ancient Christian manuscripts may reflect some of the same concerns.
When the word god does not refer to the One True God (i.e., a reference to a pagan god), the abbreviations are not usually used. For instance, the NIV translates 1 Corinthians 8:5–6 like this: “For even if there are so-called gods, whether in heaven or on earth (as indeed there are many “gods” and many “lords”), yet for us there is but one God, the Father, from whom all things came and for whom we live; and there is but one Lord, Jesus Christ, through whom all things came and through whom we live.” However, in the p46 Greek manuscript, the scribe writes out the words god and lord in verse 5 (and the NIV puts them in quotation marks), but in verse 6 the scribe uses nomina sacra for God, Father, Lord, Jesus, and Christ. (A photograph of this portion of p46 can be viewed at https://ntvmr.uni-muenster.de/manuscript-workspace?docID=10046, accessed 9/24/2022.)
The use of nomina sacra does not appear to be a space-saving technique, because many manuscripts containing it do not attempt to save space in other ways. It may be further evidence of Christian belief in the deity of Christ. The words/names God, Lord, Jesus, and Christ are all treated the same. To some degree, early Christians treated the names of Christ in the same way that Jews treated the name Yahweh. However, it does not appear nomina sacra were used with the same stringency and consistency with which Jews avoided the name Yahweh. Some manuscripts use nomina sacra inconsistently, and others not at all. This seems to demonstrate that the scribes were not attempting to “prove” anything by their use, nor were they adhering to a strict legalistic code. Rather, they were simply writing in a way that seemed natural to them.
In later manuscripts other significant words came to be abbreviated as well (son, cross, father, savior, spirit, heaven, etc.) This practice was continued in many Latin and Coptic manuscripts. What started out as a sign of respect for deity may have eventually developed into a shorthand that simply saved labor and was extended to other important words. There is still much study to be done on the reasons for and significance of nomina sacra.
Later, Christianity developed what is known as the Christogram, the symbol that combines the first two Greek letters of ΧΡΙΣΤΟΥ (“Christ”), Chi and Rho, which to English readers will look like a capital X and P. The result is a kind of monogram. The Christogram is not used in any New Testament manuscripts but is used as shorthand for Christ in later Christian writings and incorporated into Christian artwork.