'Catholic' is a word that is used in several different ways in the Christian Church.
1) With a small first letter, 'catholic' means 'applying everywhere in the Church', in other words, of 'universal' application. Thus, the 'catholic faith' is the faith shared by the whole Church. Or the whole Church from its earliest days onwards may itself be said to be 'catholic'.
2) Sometimes churches and Christians who respect the traditions of the Church as they have been handed down and developed throughout the whole of Christian history will describe themselves as 'catholic' with a small 'c'. The opposite of 'catholic' in this sense is 'reformed'. The reformed tradition puts particular emphasis on the insights into faith discovered during the Reformation of the 15th century and the patterns of church order developed at this time.
3) Sometimes 'catholic' is used to describe the mainstream, accepted version of Christian faith as opposed to teaching which is defective in some repect. In this sense 'catholic' with a small 'c' is the same as 'orthodox' with a small 'o' and is the opposite of 'heretical' where 'heresy' is teaching which is different from that accepted in the mainstream Christian churches.
4) 'Catholic' with a capital 'C' is part of the name adopted by the Roman Catholic Church and other denominations such as the Old Catholic Church (which operates as a minority church, principally in the Netherlands, Switzerland, Austria and Germany.)
© J D Yule 2003