Nomen sacrum
Nomina sacra (singular: nomen sacrum) means "sacred names" in Latin and refers to the Christian scribal practice of abbreviating several frequently occurring divine names or titles, especially in Greek manuscripts of Holy Scripture. A nomen sacrum consists of two or more letters from the original word spanned by an overline.
Metzger lists 15 such expressions from Greek papyri: the Greek counterparts of God, Lord, Jesus, Christ, Son, Spirit, David, Cross, Mother, Father, Israel, Savior, Man, Jerusalem, and Heaven. These nomina sacra are all found in Greek manuscripts of the 3rd century and earlier, except Mother, which appears in the 4th.
Nomina sacra also occur in some form in Latin, Coptic, Armenian (indicated by the ), Gothic, Old Nubian, and Cyrillic (indicated by the titlo).
Nomina sacra are consistently observed in even the earliest extant Christian writings, along with the codex form rather than the roll, implying that when these were written, in approximately the second century, the practice had already been established for some time. However, it is not known precisely when and how the nomina sacra first arose.
The initial system of nomina sacra apparently consisted of just four or five words, called nomina divina: the Greek words for Jesus, Christ, Lord, God, and possibly Spirit. The practice quickly expanded to a number of other words regarded as sacred.
In the system of nomina sacra that came to prevail, abbreviation is by contraction, meaning that the first and last letter (at least) of each word are used. In a few early cases, an alternate practice is seen of abbreviation by suspension, meaning that the initial two letters (at least) of the word are used; e.g., the opening verses of Revelation in 18 write Ἰησοῦς Χριστός (Jesus Christ) as ΙΗ ΧΡ. Contraction, however, offered the practical advantage of indicating the case of the abbreviated noun.
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