In the Catholic Encyclopedia, the entry for the term “Catholic” begins, “The word Catholic (katholikos from katholou—throughout the whole, i.e., universal) occurs in the Greek classics….” We agree that the term catholic simply means “universal.” In the early church, the terminology catholic Church was used by Christians to distinguish the true Church from those who held to the heretical teachings of Gnosticism and pantheism. The true Church is comprised of all those, regardless of their race, gender, denomination, or other religious affiliation, who place their faith in the finished work of Christ (Eph. 1:12,13), that He died for their sins, was buried, and rose again the third day (I Cor. 15:1-4). According to the Word of God, the true Church is called the Body of Christ (Eph. 1:22,23; Col. 1:18).
The Roman Catholic Church, as we know it, technically did not come into existence until 325 A.D., during the reign of Constantine, the ruler of the Roman Empire at the time. He adopted Christianity as the state religion of the empire and adopted all the trappings that eventually came with it. While Rome has always touted itself as being the “true Church,” which is universal, the very title, Roman Catholic Church is a contradiction of terms. Roman is a “specific term,” referring to those who align themselves with her unsound teachings and her pope, while the term catholic means universal. In reality, it is the Protestants who believe that the Church, the Body of Christ is catholic or universal. This universal Church would include our Roman Catholic brethren who have placed their faith solely in the finished work of Christ, and not in works or the organized church.
Rome has often pointed out that the beliefs of Protestantism are something relatively new. It claims they are merely the fruits of the Reformation, which is far from the case. We certainly agree that the Reformers were used of the Lord to confront the indiscretions and outright errors of the organized church of their day and to encourage believers to return to the Scriptures as their final authority. The Reformers, to their credit, were simply returning to biblical Christianity. Essentially, the beliefs of the Reformers were the same as the early Christians during the first three centuries of Christianity. Some of those teachings include the sole authority of the Scriptures, justification by grace alone through faith alone in Christ’s finished work alone, that there is only “one Mediator between God and men, the man Christ Jesus,” etc. Most evangelicals today, ourselves included, hold these doctrines to be among the fundamentals of the faith. source