A sacred language is a language, frequently a dead language, that is cultivated for religious reasons by people who speak another language in their daily life. In particular, a liturgical language is a sacred language.

The traditions involved in religious ritual and liturgy quite frequently provide a place where archaic forms of language occur. One of the last places the obsolescent English pronoun thou remains in frequent use is in religious liturgy; wherever the Authorised Version of the Bible is read, or older versions of the Anglican Book of Common Prayer are in use.

The use of a sacred language represents a further development of this practice. Here, language has changed so far from the language of the sacred texts that the language of the old liturgy is no longer comprehensible without special training. Missionary and pilgrim faiths may then spread the old language to populations which never spoke it, and to whom it is yet another foreign language. Once a language becomes associated with religious worship, its believers often ascribe virtues to the language of worship that they would not give to their native tongues. The sacred language is typically vested with a solemnity and dignity that speech in the vernacular lacks. The enterprise of training clergy to use and understand the sacred language becomes an important cultural investment. Their use of the tongue gives them access to a body of knowledge that untrained lay people cannot access.

A number of languages have been used as sacred languages. They include:

• Latin, for Western Europeans perhaps the sacred language par excellence, which for centuries served as the liturgical language of the Roman Catholic Church.
• Koine Greek, which plays a similar role in Greek Christianity. It differs markedly from Modern Greek, but remains half-comprehensible for Modern Greek speakers.
• Old Church Slavonic, which played a similar role in Slavic Eastern Orthodoxy.
• Church Slavonic is the current liturgical language of the Russian Orthodox Church.
• Sanskrit, a learned but still living tongue, the tongue of the Vedas and other sacred texts of Hinduism as well as the original language of Mahayana Buddhism.
• Pali, the original language of Theravada Buddhism.
• Avestan, the language of the Avesta, the holy book of Zoroastrianism.
• Classical Arabic, for Muslims the only true language of the Qur'an; it differs markedly from the various forms of contemporary spoken Arabic.
• Classical Chinese, the language of older Chinese literature and the Confucian, Taoist, and in East Asia also of the Buddhist sacred texts, which also differs markedly from contemporary spoken Mandarin.
• Hebrew, the language of the Hebrew Bible used in the liturgy of Judaism
• Etruscan, cultivated for religious and magical purposes in the Roman Empire.
• Palaic and Luwian, cultivated as a religious language by the Hittites.
• Sumerian, cultivated long after its extinction in Assyria and Babylon.
• Yorùbá, the language of the Yorùbá people, brought to the New World by African slaves, and preserved in Santería, Candomblé, and other transplanted African religions.
• Ge'ez, an older variety of Amharic, used as a liturgical language by Ethiopian Christians.
• Coptic, the most recent form of the Egyptian language, used in the liturgy of Coptic Christians.
• Aramaic, the language spoken by Jesus, used as a liturgical language by Syrian Christians and, in a Hebrewized form, as a language of teaching and study in Judaism.
• Mandaic, an Aramaic language, in Mandaeanism
• Various Native American languages are cultivated for religious and ceremonial purposes by Native Americans who no longer use them in daily life.
• Ladino as a Hebraicized form of Judaeo-Spanish was used for Bible translations by Sephardis.
• The Kakure Kirishitiyan (Hidden Christians) of Japan retained some prayers in Portuguese and Latin that they recited without understanding the language.
• High German is used in Amish communities for Bible readings and sermons

See also

• literary language
• official language
• standard language