The second rung of the ladder is to know how to accurately interpret the Bible, that is to accurately gauge the message contained therein, and only one institution has ever been established who can do so. That is the Holy Catholic Church, which the Bible itself points to.
In the Gospel of St. Matthew, Jesus founds His Church upon St. Peter, as is clear from many passages, not the least of which are the following:
St. Matthew 16:18-19: "And I say to thee: That thou art Peter; and upon this rock I will build my church, and the gates of hell shall not prevail against it. And I will give to thee the keys of the kingdom of heaven. And whatsoever thou shalt bind upon earth, it shall be bound also in heaven: and whatsoever thou shalt loose upon earth, it shall be loosed also in heaven."
Jesus, in very specific language, gives St. Peter the authority to bind and loose, that is, to exercise such a powerful authority on earth that when he does so, his effects of his actions will translate even to heaven. Jesus also clearly admonishes his followers to heed the church's judgement.
St. Matthew 18:17: "And if he will not hear them: tell the church. And if he will not hear the church, let him be to thee as the heathen and publican."
Though the Bible does not explicitly state that St. Peter was the bishop of Rome, the writings of Early Church Fathers make it clear this was the case. The Bible does, however, lay out clear irrefutable evidence that St. Peter was the first supreme Pontiff over the church, the head bishop of the Church, the Pope, which means father. He was appointed by Christ as the spiritual Father over His Church on earth.
Before we go any further, many Protestants will object here, citing the following verse as proof that this is an unbiblical doctrine:
St. Matthew 23:9: "And call none your father upon earth; for one is your father, who is in heaven."
The problem with their false claim, however is that there are numerous examples in the New Testament of the term 'father' being used as a form of address and reference, even for men who are not biologically related to the speaker. There are, in fact, so many uses of "father" in the New Testament, that the Fundamentalist interpretation of Matthew 23 (and the objection to Catholics calling priests 'father') must be wrong, as we shall see from a few quick examples.
St. Paul regularly referred to Timothy as his child: "Therefore I sent to you Timothy, my beloved and faithful child in the Lord, to remind you of my ways in Christ" (1 Cor. 4:17); "To Timothy, my true child in the faith: grace, mercy, and peace from God the Father and Christ Jesus our Lord" (1 Tim. 1:2); "To Timothy, my beloved child: Grace, mercy, and peace from God the Father and Christ Jesus our Lord" (2 Tim. 1:2).
He also referred to Timothy as his son: "This charge I commit to you, Timothy, my son, in accordance with the prophetic utterances which pointed to you, that inspired by them you may wage the good warfare" (1 Tim 1:18); "You then, my son, be strong in the grace that is in Christ Jesus" (2 Tim. 2:1); "But Timothy’s worth you know, how as a son with a father he has served with me in the gospel" (Phil. 2:22).
St. Paul also referred to other of his converts in this way: "To Titus, my true child in a common faith: grace and peace from God the Father and Christ Jesus our Savior" (Titus 1:4); "I appeal to you for my child, Onesimus, whose father I have become in my imprisonment" (Philem. 10). None of these men were St. Paul’s literal, biological sons. Rather, St. Paul is emphasizing his spiritual fatherhood with them.
So what did Jesus mean? Jesus criticized Jewish leaders who love "the place of honor at feasts and the best seats in the synagogues, and salutations in the market places, and being called ‘rabbi’ by men" (Matt. 23:6–7). His admonition here is a response to the Pharisees’ proud hearts and their grasping after marks of status and prestige.
He was using hyperbole (exaggeration to make a point) to show the scribes and Pharisees how sinful and proud they were for not looking humbly to God as the source of all authority and fatherhood and teaching, and instead setting themselves up as the ultimate authorities, father figures, and teachers.
Christ used hyperbole often, for example when he declared, "If your right eye causes you to sin, pluck it out and throw it away; it is better that you lose one of your members than that your whole body be thrown into hell" (Matt. 5:29, cf. 18:9; Mark 9:47). Christ certainly did not intend this to be applied literally, for otherwise all Christians would be blind amputees! (cf. 1 John 1:8; 1 Tim. 1:15). We are all subject to "the lust of the flesh and the lust of the eyes and the pride of life" (1 John 2:16).
Since Jesus is demonstrably using hyperbole when he says not to call anyone our father—else we would not be able to refer to our earthly fathers as such—we must read his words carefully and with sensitivity to the presence of hyperbole if we wish to understand what he is saying.
As the apostolic example shows, some individuals genuinely do have a spiritual fatherhood, meaning that they can be referred to as spiritual fathers. What must not be done is to confuse their form of spiritual paternity with that of God. Ultimately, God is our supreme protector, provider, and instructor. Correspondingly, it is wrong to view any individual other than God as having these roles.
Now that we have overcome this clearly illogical objection of the Protestants, we will move on and see that the first Pope was given the gift of an unfailing faith, or infallibility.
St. Luke 22:31-32: "And the Lord said: Simon, Simon, behold Satan hath desired to have you, that he may sift you as wheat: But I have prayed for thee, that thy faith fail not: and thou, being once converted, confirm thy brethren."
This does not mean that St. Peter was perfect, could not sin and could not make mistakes, but it meant that when he spoke on a matter of faith and morals with the intention of binding all Christians to obedience, then in such a case he was protected from making any error against the faith.
Finally, after St. Peter's three denials of the Lord, he was three times confirmed in his supremacy over the whole of Christ's flock, the Church, by Jesus Christ Himself.
St. John 21:15-17: "When therefore they had dined, Jesus saith to Simon Peter: Simon son of John, lovest thou me more than these? He saith to him: Yea, Lord, thou knowest that I love thee. He saith to him: Feed my lambs. 16 He saith to him again: Simon, son of John, lovest thou me? He saith to him: Yea, Lord, thou knowest that I love thee. He saith to him: Feed my lambs. He said to him the third time: Simon, son of John, lovest thou me? Peter was grieved, because he had said to him the third time: Lovest thou me? And he said to him: Lord, thou knowest all things: thou knowest that I love thee. He said to him: Feed my sheep."
Other clear proof that He Who inspired the authors of Scripture intended for St. Peter to be the supreme head of the Church is as follows:
St. Peter's name is always the first when the Apostles are listed (St. Matthew 10:2-4, St. Mark 3:16-19, St. Luke 6:14-16, Acts of the Apostles 1:13).
St. Peter is always singled when the Apostles are mentioned together as a group (St. Mark 16:7, St. Luke 9:32).
St. Peter spoke for all the Apostles (St. Matthew 18:21, St. Mark 8:29, St. Luke 8:45, 12:41, St. John 6:69)
St. Peter's name occurs around 200 times in the New Testament, more than all the other Apostles combined. There is a very good reason why God inspired the New Testament writers to always place the name of St. Peter first among them, and Judas' name last. It is because St. Peter, and those who would succeed him, was given the position of highest authority in the Church next to Christ, by Christ Himself.
The Church described in the Bible consists of a visible hierarchy of bishops, who are the Apostles and their successors, and this is consonant with the Holy Catholic Church. This is because the Church of the Bible and the Holy Catholic Church are one and the same Church.
Let's start with Judas, since he was the first of the Apostles to die and need to be replaced.
Acts Of Apostles 1:16-17, 20, 26: "Men, brethren, the scripture must needs be fulfilled, which the Holy Ghost spoke before by the mouth of David concerning Judas, who was the leader of them that apprehended Jesus: Who was numbered with us, and had obtained part of this ministry... For it is written in the book of Psalms: Let their habitation become desolate, and let there be none to dwell therein. And his bishopric let another take... And they gave them lots, and the lot fell upon Matthias, and he was numbered with the eleven apostles."
So we see that to be "numbered with the eleven Apostles" was to be counted as taking over the bishopric of Judas. There are a few other quotes in the Bible which make specific mention of the office of bishop:
Acts Of Apostles 20:28: "Take heed to yourselves, and to the whole flock, wherein the Holy Ghost hath placed you bishops, to rule the church of God, which he hath purchased with his own blood."
Philippians 1:1: "Paul and Timothy, the servants of Jesus Christ; to all the saints in Christ Jesus, who are at Philippi, with the bishops and deacons."
1 Timothy 3:1: "A faithful saying: if a man desire the office of a bishop, he desireth a good work."
Titus 1:7: "For a bishop must be without crime, as the steward of God: not proud, not subject to anger, not given to wine, no striker, not greedy of filthy lucre:"
1 St. Peter 2:25: "For you were as sheep going astray; but you are now converted to the shepherd and bishop of your souls."
The reason that this hierarchy of bishops is so important to the Church of Christ is twofold:
First, the Apostles and their successors, being the men appointed by Christ to carry out His mission of evangelizing and teaching the world (St. Matthew 28:19-20), were given authority to establish certain disciplines in order to foster piety, and to teach doctrines which Jesus did not fully expound publicly, but rather only revealed in their fullness to the Apostles themselves, and the Bible shows this to be so.
John 21:25: "But there are also many other things which Jesus did; which, if they were written every one, the world itself, I think, would not be able to contain the books that should be written."
The Apostle St. John is here telling us that what Jesus did is not wholly contained in Scripture alone. This is important because there are doctrines which are revealed more fully revealed through the exposition of the traditions of the Apostles.
2 Thessalonians 2:14: "Therefore, brethren, stand fast; and hold the traditions which you have learned, whether by word, or by our epistle."
2 Thessalonians 3:6: "And we charge you, brethren, in the name of our Lord Jesus Christ, that you withdraw yourselves from every brother walking disorderly, and not according to the tradition which they have received of us."
St. Paul was so insistent on adherence to the tradition of the Apostles, that he exhorted the people to avoid any who rejected it.
Second, without the successors of the Apostles, the bishops, there would be no competent guides to properly interpret the Holy Scriptures, and people would very easily be led into error. The Bible itself tells us this is so.
In talking about the letters of St. Paul, which make up a sizable portion of the New Testament in Holy Scripture, St. Peter says the following:
2 Peter 3:16: "As also in all his epistles, speaking in them of these things; in which are certain things hard to be understood, which the unlearned and unstable wrest, as they do also the other scriptures, to their own destruction."
He is here addressing the people and warning them that it is certainly possible, even likely that those who interpret the Scriptures on their own without the guidance of the learned, will do so to their own destruction, not holding to the true meaning which the authors meant to convey. This truth is further expressed in Scripture.
Acts of the Apostles 8:29-31: "And the Spirit said to Philip: Go near, and join thyself to this chariot. And Philip running thither, heard him reading the prophet Isaias. And he said: Thinkest thou that thou understandest what thou readest? Who said: And how can I, unless some man shew me? And he desired Philip that he would come up and sit with him."
The Lord inspired the Apostle Philip to go and instruct the eunuch, who was unable to understand the Scriptures without an authoritative guide.
The only Church in the world that recognizes the supreme authority of St. Peter and his successors is the Holy Catholic Church, outside of which there is no salvation, nor remission of sins. It is the will of God, that all men enter His Church and worship Him as He has ordained, so that they may not perish, upon their natural death, but enter into eternal life.
Ephesians 2:19-22: "Now therefore you are no more strangers and foreigners; but you are fellow citizens with the saints, and the domestics of God, Built upon the foundation of the apostles and prophets, Jesus Christ himself being the chief corner stone: In whom all the building, being framed together, groweth up into an holy temple in the Lord. In whom you also are built together into an habitation of God in the Spirit."