The title says it all. Rome and the East claim to be the oldest churches on earth, arguing that they pre-existed the Protestants by fifteen hundred years. I do not argue that they are old churches, with many traditions and practices that go back many, many centuries. However, Reformed Protestantism is older, more ancient, and more venerable than both of these groups.
There is an objective test whereby we can examine the claims of the various churches. That objective test is the teaching of the Bible, which predates Rome and the East. The faith clearly set forth within its pages, being the faith of the prophets and the apostles, is authentic Christianity. Rome and the East fail that test. They have departed form the faith once delivered to the saints, not just in ceremonies, but in giving honour to images, Mary, and other dead people. They have departed from the faith in making free will the crux of man’s salvation, rather than the free grace of God. They have erred in defacing the sacraments of baptism and the Supper, so that they have become something different from what Christ instituted and ordained.
Reformation Protestantism goes further back than the fathers and tradition, right back to the apostles and apostles. Its authority is more ancient than Rome and the Eastern churches.
So then, while Rome and the East are old churches, they are not as ancient as biblical Protestantism.