Catholics believe that The Church is visible, spiritual and founded by Jesus. This is a mystery of the faith. The Word of God tells us this otherwise there would be no way to understand this through reason. If we were to say that there is no salvation outside Jesus, all Christians, Catholics included, would agree. Since Jesus is the head of His Church, the Catholic Church, one may fully say that there is no salvation outside the Church, meaning the Catholic Church. This statement is often met with derision and accusations of arrogance despite both statements meaning the same thing. In order for someone to be saved they must be Baptized into Christ.
Objection 1: Christ did not establish the Catholic Church.
Well let’s take a look at Matthew 16:18 “And I tell you, you are Peter, and on this rock I will build my church, and the powers of death shall not prevail against it.” It is quite clear that the Church was built upon Peter (Cephas, Petros, rock). If we take a look at the Expositor’s Bible Commentary, a clearly non-Catholic commentary, D.A. Carson agrees with this position. This same Church, founded on Peter the first Pope of the Catholic Church, is shown to not be able to commit errors of Doctrine (“and the powers of death shall not prevail against it”). This same Church is the Church we today call the Catholic Church.
Ignatius of Antioch, a martyr for the faith, disciple of John the apostle, appointed as the Episcopal See of Antioch by Peter and possibly one of the children that Jesus took in his arms and blessed (by tradition) said:
"Let no one do anything of concern to the Church without the bishop. Let that be considered a valid Eucharist which is celebrated by the bishop or by one whom he ordains [i.e., a presbyter]. Wherever the bishop appears, let the people be there; just as wherever Jesus Christ is, there is the Catholic Church" (Letter to the Smyrneans 8:2 [A.D. 110]).
And Polycarp, another martyr of the faith, disciple of John the apostle, a friend from youth of Ignatius, Bishop of Smyrna said:
"And of the elect, he was one indeed, the wonderful martyr Polycarp, who in our days was an apostolic and prophetic teacher, bishop of the Catholic Church in Smyrna. For every word which came forth from his mouth was fulfilled and will be fulfilled" (Martyrdom of Polycarp 16:2 [A.D. 155]).
This shows just a glimpse of the historical record of the Catholic Church being the historical Church of Christ. This same Church is the Church talked about in the Apostle’s Creed.
Objection 2: It is arrogant to say that there is no salvation outside the Catholic Church, any Christian may be saved.
It would only be arrogant if it were not true. As shown in Objection 1, Christ established the Catholic Church. Any Christian may be saved as well if they are Baptized since that is the entrance into Christ. Again, no Christian would disagree that there is no salvation outside of Christ and since Christ established a Church, which is the Catholic Church, then it follows that one must be part of the Catholic Church. However, the Catechism of the Catholic Church gives us what is called an extraordinary mode of salvation:
CCC 847: “This affirmation is not aimed at those who, through no fault of their own, do not know Christ and his Church.”
In other words, if a person through no fault of their own, invincible ignorance, does not come to the realization that the Catholic Church is the True Church they are not held accountable to this. An example of this would be an evangelist preaching a Gospel which the potential convert does not understand or cannot come to a reasonable conclusion that it is the Truth. It could also mean that the potential convert may not have the mental capacity to understand the Gospel due to circumstances out of their control.
This form of extraordinary salvation does not alleviate the potential convert if they come to know the Truth and continue on a path divergent from the Truth. Such as the potential convert reasonably knowing that the Catholic Church is the True Church but because of scandals in the Church they reject the Church. This would be a rejection of Christ and no Christian would hesitate to say if one were to reject Christ they in turn also reject salvation.
Objection 3: If there is no salvation outside of Jesus, then surely all non-Christians are condemned to hell. This is a rather exclusive group of people that are saved.
CCC 843: “The Catholic Church recognizes in other religions that search, among shadows and images, for the God who is unknown yet near since he gives life and breath and all things and wants all men to be saved. Thus, the Church considers all goodness and truth found in these religions as "a preparation for the Gospel and given by him who enlightens all men that they may at length have life”
This topic describes anyone that is not Baptized (Born Again) in the manner prescribed by the Bible. It is a rather exclusive group of people that will be saved but not exclusive in the fact that only Christians can be saved. The Catholic Church teaches that salvation is available to everyone who desires salvation knowingly or not. This is called soteriological inclusivism since “This is good, and it is acceptable in the sight of God our Savior, 4 who desires all men to be saved and to come to the knowledge of the truth” (1 Timothy 2:3-4) and “"The Lord is not slack concerning his promise, as some men count slackness; but is longsuffering to us, not willing that any should perish, but that all should come to repentance" (2 Peter 3:9).
St. Thomas Aquinas calls this “Baptism of Desire” in which someone who desires to be part of the Body of Christ, at death, becomes part of the Body of Christ through the Grace of Christ. In light of these passages, among others, it is unreasonable to say that God does not want certain people to be saved. It is also unreasonable for God to not give the opportunity for certain people to be saved despite His foreknowledge of whether they will choose salvation or not. Rather it is more reasonable that certain people will never be preached the Gospel yet try with all their might to follow the natural law. These people are not saving themselves but instead it is through Christ’s mercy and grace that they are able to be saved.
CCC 847 also applies in this case.
In fact, it would seem unreasonable that the Catholic Church be called “catholic” (universal) if this principle did not apply since the Church would not in fact be universal. Only through Christ’s mercy and grace can the Church indeed be universal.
Objection 4: If anyone can be saved then there is no need of the Catholic Church.
This is an untrue statement. It assumes that the Catholic Church was not established by Jesus but since, as I have shown in Objection 1, it was established by Jesus then it is a necessity.
CCC 848: "Although in ways known to himself God can lead those who, through no fault of their own, are ignorant of the Gospel, to that faith without which it is impossible to please him, the Church still has the obligation and also the sacred right to evangelize all men."
Each Christian has an obligation to evangelize and since the Catholic Church is the True Church of Christ then it follows that Catholics need to evangelize even among Christian denominations. This is the purpose of the Church, to bring people to the truth and salvation, in other words to Christ.
If you have a suggestion for an apologetic article please leave a comment and I will do my best to get to it or a similar topic. I will also credit you with the question.