Roman Catholics insist they are the "original" church established personally by Christ with Peter as it's first pope. How does one explain that error to Catholic friends and loved ones who have been taught this from a very young age? How do we explain to them that theirs is NOT the "one true church" and that it does NOT teach and reflect faith in Christ and the Bible but is a man-made religion in complete opposition to Christ and the Bible? Where does one start?
Here are a couple of paragraphs of an article I found to be very informative and maybe it will help you as well...
"The writers of the New Testament taught that salvation came through simple faith in Jesus Christ. They taught that saving faith is an immediate experience with Christ, and that all men are capable of coming directly to Christ. There was no external institution necessary, no human priest or religious rite was required to qualify a man for coming to Christ and receiving forgiveness and eternal life. New Testament Christianity also taught that a New Testament Church was a body of persons who had been born again (read John chapter 3), had been baptized, and possessed the Spirit of Christ. All Churches were on the same level, and each possessed authority to govern its own affairs without outside interference.
But during the second and third centuries this began to be changed. Water baptism began to be considered as having some saving power. Justin Martyr, about the year 165, wrote that baptism completes salvation. Irenacus, writing about 185, boldly declared that baptism is the new birth and brings regeneration.
Irenacus' writings gave the first hint that perhaps infants were at that time subjects of baptism, which would be the natural thing to follow if water baptism brings salvation.
Ignatius wrote, about 115, that the bread and the wine of the Lord's Supper were the "medicine of immortality." perhaps speaking in symbolical language. However, by the time of Irenacus, in the last part of the century, the teaching was flatly being made that after the bread had been consecrated it was no longer common bread. They began to believe that in some way the consecrated bread was now able to convey spiritual grace to men. This had never been taught by the apostles of Christ, not by Christ Himself.
There is no indication whatever in the writings of the first century that the Church at that time considered baptism or the Lord's supper to be anything other than symbolical memorials. They were simply pictures of spiritual truths. However, when it came to be believed that baptism and the Lord's supper were the means of imparting salvation and spiritual blessing, then the pastor, or the priest, as he then came to be called, had a power over the people which he had not previously had.
The Jewish system and also the ancient pagan cults required priests and ritual as a part of their religious worship. The introduction of the need for magical words to be said over bread and wine, etc., brought the necessity to secure men as priests for the Churches who were trained and qualified to administer these "sacraments," as they were now called. It came to be believed that only the bishop, or the priests who had been trained and authorized by him, could effectively administer baptism and perform the "magic" of changing the bread and wine into the actual body and blood of Christ. This of course gave a new power to the bishops and the priests over the people.
This new conception of baptism and of the Lord's supper made a great difference in the conception of what the Church was. In the New Testament, the Church consisted of the people in a local body. The leaders were on the same level with the people, but served because they were given special gifts by the Holy Spirit. The ordinances were not magical but symbolical. This conception had now entirely changed. Also, the original equality among the various pastors, bishops, or presbyters serving in the church began to disappear.
In the New Testament Church there was no difference in office between a bishop and a presbyter, these two names describing the same office. But quite early in the second century it became common for one of the ministers to assume leadership. This was sometimes because of extra ability, strong personality, or maturity. Also, no doubt the natural impulse to advance one's self had a great part in this taking place."