Perhaps the biggest claim to fame of the RCC is that it is THE church established by Jesus. It claims an unbroken history back to the Apostles.
"Among the Christian churches, only the Catholic Church has existed since the time of Jesus. Every other Christian church is an offshoot of the Catholic Church."
-excerpt from Catholic.com
"152. Which is the one true Church established by Christ?
The one true Church established by Christ is the Catholic Church.
(a) Many churches which claim to be Christian have broken away from the one true Church established by Jesus Christ. These churches were founded by men who had no authority from God to found a church.
(b) Christ intended that there should be only one true Christian Church, for He always spoke of His Church as one."
-The Baltimore Catechism (#3, lesson 12)
The Baltimore Catechism goes on to say that “We know that the Catholic Church is the one true Church established by Christ because it alone has the marks of the true Church… Jesus Christ willed that the true Church should have these marks, which would distinguish it from all false religions”
According to the catechism, the “chief marks of the true church” are the following:
1. The Church is One
"… Our Divine Savior prayed explicitly that His Church might be one, and He made it one; thus men can recognize it as the true Church…
… There are many religious sects which claim to be Christian, but are separated from the unity of Christ by their rejection of the authority invested by Him in the Roman Pontiff, the successor to Saint Peter…" Baltimore Catechism
"Jesus established only one Church, not a collection of differing churches (Lutheran, Baptist, Anglican, and so on). The Bible says the Church is the bride of Christ (Eph. 5:23–32). Jesus can have but one spouse, and his spouse is the Catholic Church." excerpt from Catholic.com
2. The Church is Holy
"The Catholic Church is holy because it was founded by Jesus Christ, who is all-holy, and because it teaches, according to the will of Christ, holy doctrines, and provides the means of leading a holy life, thereby giving holy members to every age." Baltimore Catechism
"But the Church itself is holy because it is the source of holiness and is the guardian of the special means of grace Jesus established, the sacraments (cf. Eph. 5:26)." excerpt from Catholic.com
3. The Church is Catholic
"The Catholic Church is catholic or universal because, destined to last for all time, it never fails to fulfill the divine commandment to teach all nations all the truths revealed by God." Baltimore Catechism
4. The Church is Apostolic
"The true Church is apostolic because it is the Church Christ founded upon the apostles, and especially upon Peter whom He called the Rock on which the Church would be built. The supreme power of Saint Peter in the Church has been passed down through the unbroken line of his successors in the see of Rome." Baltimore Catechism
"The apostles were the first bishops, and, since the first century, there has been an unbroken line of Catholic bishops faithfully handing on what the apostles taught the first Christians in Scripture and oral Tradition (2 Tim. 2:2)...
…Early Christian writings prove the first Christians were thoroughly Catholic in belief and practice and looked to the successors of the apostles as their leaders. What these first Christians believed is still believed by the Catholic Church. No other Church can make that claim." excerpt from Catholic.com
I will write more later on this idea of “the one true church” as it is key to the discussion of whether or not Rome teaches “another gospel”. But for the next post I would like to talk more about the structure/hierarchy of the church.