Let's discuss the differences between Catholics and Protestants. The real difference come down to authority. For Biblical Protestants, the authority is the Word of God. A priest once summed it up very well when he said, "You Protestants believe everything the book says!"
The Biblical emphasis which is the heritage of the Protestant churches is visable even in the archecture of it's buildings. In the Catholic church the altar is central. There the sacrifice of Christ is believed to be renewed in the mass. In the Protestant churches the pulpit is the center of attention. It is essentially a stand to hold the Bible in a position where it is easy for the preacher to read because the reading and explanation of the Word of God is central.
The Catholic church does offically accept the Bible as the inspired Word of God, but not as the final authority. Tradition, along with the pronouncements of Popes and Councils is considered equally authoritative. There are, however, many points in which the tradition of the Catholic church is not in agreement with the Bible. It is at these points that each one of us must decide which he will follow.
In deciding whether to submit to the authority of the Bible or that of the Church, we need to take into consideration the fact that what the RCC believes to be right or wrong changes with the passing of time. To have communion service in the language of the people was, at one time a Protestant heresy. The mass had to be said in Latin. Then came a period of reform started by Pope John XXIII, when it had to be in the languages of the people instead. The Bible, however, does not change and therefore cannot always agree with a changing church.
An elderly Catholic lady once said, "If the Pope wants to eat meat on Fridays and go to hell, he can, but I'm not going to!" Since the Bible agrees with the present Catholic doctrine that eating meat on Fridays is not sin, it could not agree earlier that eating meat on Fridays was sin.
Down through the centuries, many changes have also entered into the church's teaching which are strongly in disagreement with the Bible. I might illustrate this with the acceptance of the veneration of images in the church. Differences between Catholic doctrine, and that of those for whom the Bible is the final authority do not result from a Protestant desire to be obnoxious, but rather from the fact that where there is a conflict between the teachings of the Bible and those of the RCC, it is impossible to accept both. Each person must choose in these points which authority he will obey.
For the most part, the traditions are in contrast with the Bible began to form after 300 A.D. in the time of the Roman emperor Constantine, and gradually developed until they became dogmas of the church, though a few of the ant-biblical doctrines are very resent.
A more recent development, and one which is harder to evaluate is that of the ecumenical movement which, when it first began, was not in the RCC. It started in the liberal (also called modernist) wing of the Protestant churches; that is, among those Protestant churches which no longer really believed the Bible. As a result they no longer had a clear message to offer. The result was that the liberal churches started to diminish in attendance.
Where a large congregation had been easily able to maintain it's large church building, a smaller group was now having trouble. Often this was also true of the church of another liberal denomination just around the corner. Why not get together, put both congregations in one of the the buildings, sell the other, and solve the economic problems of the diminishing churches? Thus practical financial motivation as well as the desirability of oneness combined to begin the ecumenical movement among the Protestant churches.
The RCC found itself attracted to the ecumenical ideal of unity, but it had a practical motivation as well, that of offering the RCC as the one fold into which all denominations should come. To prepare a Catholicism into which Protestants might feel more free to enter, Bible reading began to be encouraged among Catholics, and changes were made in the RC liturgy to make it more like what Protestants were used to.
Unfortunitly, however, in their desire to be like Protestants, many Catholic seminaries began teaching the philosophes of the liberal theologians who had led so many Protestant churches away from the Bible. The results were the same. Roman Catholic church attendance started to diminish too, giving the RCC the same powerful practical financial motivation for combining churches that the liberal Protestant groups had.
While the influence of the Bible has been increasing among some Catholics because they are reading it more now that the church permits it, other Catholics are being swayed by liberal attacks on the Bibles truthfulness.
Another new development in the Catholic church which has also come to it from Protestants is the Charismatic movement which started in a Protestant church in California in 1901. It gave rise first to the Pentecostal churches, and then, spilled across denominational lines, to the Catholic Charismatic movement.
Down through the centuries the Bible has been hated and destroyed as no other book. Probably more copies of the Bible have been burned than of all other books put together, yet today more people read it, more people own it, and it is translated into more languages and published in more copies than any other book.
Not only do millions read this book today, but millions of others in the past have given their lives to make its message known. Why?
Because it has made sinful lives good and worthwhile. Through its influence they have come to know God and to be a help to those around them.
Because it is inspired of God. All Scripture is given by inspiration of God... (2 Timothy 3:16). In addition to saying so, it gives convincing evidence of really being inspired by God; for example many of it's prophecies have already been fulfilled. Catholic doctrine also states that this book is inspired of God.
The Bible contains everything that is necessary to bring the Christian to perfection. The verse quoted above continues, All Scripture is given by inspiration of God, and is profitable for doctrine, for reproof, for correction, for instruction in righteousness: That the man of God may be perfect, throughly furnished unto all good works (2 Timothy 3:16-17). We need add nothing from tradition to bring the believer to this fully complete and equipped state.
Because, as the apostle Peter informs us in his second letter, the Bible is more reliable than that which he had seen with his eyes and heard with his ears because it was written by men impelled by the Holy Spirit (2 Peter 1:16-21). It would seem obvious that if the Bible is more reliable than what Peter himself has seen or heard, it is also more reliable than any tradition which contradicts it.
Some misinterpret a part of this Scripture and say that only the RCC is capable of interpreting the Bible. The passage, however, speaks of God's guidance of those who wrote the Bible, and does not say that only certain ones can interpret it. The apostle Paul praised the believers of Berea for examining the Scriptures for themselves to see if what he was teaching them was really Scriptural: Those were more noble than those in Thessalonica, in that they recieved the word with all readiness of mind, and searched the scriptures daily, whether those things were so (Acts 17:11). If they did well to test the teachings of the apostle Paul by comparing them with the Scriptures that they already had, how much more should we apply the same test to the traditions of the church today?
The New Testament speaks a great deal of tradition, and condemns it when it is contrary to the word of God. Jesus said: Full well ye reject the commandment of God, that ye may keep your own tradition... Making the word of God of none effect through your tradition, which ye have delivered: and many such like things do ye (Mark 7:9,13; also see Matthew 15:2-6; Colossians 2:8; 1 Thessalonians 2:13; Galatians 1:14).
Some, trying to justify the authority of the Catholic church over that of the Scriptures, remind us that the Bible does not contain everything that Jesus and the apostles taught. This is certainly true and the Bible itself affirms it. This fact, however, gives us no authorization to accept the many Catholic doctrines which are explicitly contrary to the teachings of Scripture (Revelations 22:18-19; Mark 7:3-13). The Bible contains all that is needed to bring us to faith in Christ, and to help us grow in that faith. (John 20:30-31; 2 Timothy 3:16-17).
The great majority of the differences between Bible believing Protestants and the RCC do not come from different interpretations of the Bible or different Bibles, but from a difference in what is the "final authority". The Bible must be interpreted in the light of the Bible itself and neither twisted nor set aside to honor the pronouncement of Popes, Councils, or Tradition (2 Thessalonians 2:15; 3:6).
From Answers to my Catholic Friends by Thomas F. Henze