Data source: Gina A. Zurlo and Todd M. Johnson, eds., World Christian Database (Leiden/Boston: Brill, 2024).
| Glossary item | Definition |
|---|---|
| conversations | In ecumenical terminology, discussions between churches or denominations where as yet no organic union is publicly envisaged nor constitutional questions discussed. |
| conversion | The change from one belief, faith or religion to another. |
| conversion | A change in a person’s allegiance or membership in one religion to allegiance or membership in another. |
| conversion change | Change in religious allegiance in a country or body, i.e. the annual net aggregate of conversions to the body of new adherents from other religions or religious bodies minus defections (sometimes termed apostasies) from it of former adherents leaving to join other religions or religious bodies. |
| Conversos | Marranos (qv). |
| convert | A person converted to a religious belief, faith or religion from another religion. |
| converted | The state of having been converted to faith in Christ. |
| converted Christians | Those who have had, or claim to have had, an experience of conversion to Christ committed Christians (qv). |
| converts | Persons who have become followers of a religion, leaving their former religion or nonreligion. |
| conveyors | See decision-makers. |
| conviction | In evangelization, the state or extent of a population being convinced or persuaded or compelled to admit the truth of the gospel. |
| co-operative | (broader than credit union). An enterprise or organization owned by and operated for the benefit of those using its services. |
| Coptic | Tradition dating back to Apostolic era, now referring to Egyptians in the Coptic Orthodox, Coptic Catholic, and Coptic Evangelical churches. |
| Coptic Calendar | Calendar of the Coptic Orthodox Church, and still used also by the government of Egypt for agricultural events (planting, harvesting); begun AD 284 at end of the age of martyrdom, 12 months each of 30 days each year; thus AD 2000 = Coptic 1716. |
| Coptic Orthodox Patriarchate of Alexandria | Oriental Orthodox. |
| Coptic rite | Catholic rite for Egyptian Copts under Rome. |
| co-religionist | A person having the same religion as another. |
| co-responsibility | In Catholic usage, church government through all levels of the church, involving priests, religious personnel and laity in the whole process of consultation and decision-making. |
| co-responsible evangelization | In Catholic usage, evangelization shared among the various ranks of clergy and laity. |
| corporately-evangelized | A society or people who have been evangelized not individually but collectively, together with their traditions and institutions. |
| corps | In Salvation Army usage, a center for the propagation of the gospel under one or more officers. |
| correspondence courses | In this field, there are over 370 Christian centers and organizations significant at the national or wider levels. |
| cosmoreligion | A universal (non-local) religion open to all, with over 200 million adherents. |
| cost-effectiveness | As a comparative measure, the total cost, to Christians in a country, of baptizing one person. |
| council | An assembly of ecclesiastics or church representatives convened to discuss matters of doctrine, discipline, law, morals, etc. |
Data on 18 categories of religion, including non-religious, by country, province, and people.
Data on all religions, Christian activities, and trends.
Membership data, year begun, and rates of change.
Population and religion data on all major cities & provinces.
Detailed information covering religion, culture, and geography.
A repository of historical data, including a chronology of Christianity from the 1st to 21st centuries.