The word “pope” and also the word “patriarch” (usually applied to bishops in Eastern Catholicism or Eastern Orthodoxy) both derive from the ancient Greek word páppas, originally an affectionate term meaning “father.” The earliest record of the use of this title is in regard to the Patriarch (“Pope”) Heraclas of Alexandria (232–248). In the early third century, the title was applied to all bishops. The earliest instance of pope being used of the bishop of Rome also dates to the third century, when it was applied to Pope Marcellinus.

As with many other technical or titular terms not found in the Bible (either in English or Greek), such as “Trinity,” “original sin” and “virgin birth,” the concept is present, whether or not one particular term or title is. We see the concept of pope applied to Peter, by the Church Fathers above, in commenting on biblical Petrine passages. The New Testament was written in Koine Greek, the common language spoken after the conquests of Alexander the Great in the fourth century BC, during the Hellenistic period, in the Roman Empire and in the early Byzantine Empire. It replaced the ancient Greek dialects.

The word páppas was an Ancient Greek term. The later form of this word, pápas — or “pope” (Latin, papa) was present in Late Koine Greek and Byzantine Greek. So it isn’t found in the New Testament, which used language that was later than Ancient Greek and before Late Koine Greek. This explains why it doesn’t appear in historical Christian use until the early third century AD.

But of course, the concept is there in the Bible, and the usual word used for “father” is pater. It’s translated as “father” 418 times in the King James Version. Like virtually all biblical words, it has multiple meanings, but one of them is “spiritual father or guide” or “one who infuses his spirit into others.” This meaning could be construed as “papal.” And so we see St. Paul using it in this manner:

1 Corinthians 4:15-16 (RSV) For though you have countless guides in Christ, you do not have many fathers. For I became your father in Christ Jesus through the gospel. I urge you, then, be imitators of me.

Philippians 2:22 But Timothy’s worth you know, how as a son with a father he has served with me in the gospel.

1 Thessalonians 2:11-12 For you know how, like a father with his children, we exhorted each one of you and encouraged you and charged you to lead a life worthy of God, who calls you into his own kingdom and glory.

Therefore, in this sense of theological and spiritual guidance, St. Paul was a “father” (or “pope,” originally meaning the same thing) to the Corinthian and Thessalonian congregations, and to Timothy. The same concept in different words occurs when St. Paul calls Timothy “my son” twice (1 Timothy 1:18; 2 Timothy 2:1), “my true child in the faith” (1 Timothy 1:2), and “my beloved and faithful child in the Lord” (1 Corinthians 4:17).

Paul is even more descriptive along these lines, in another related passage:

Philemon 1:10-13 I appeal to you for my child, Onesimus, whose father I have become in my imprisonment. (Formerly he was useless to you, but now he is indeed useful to you and to me.) I am sending him back to you, sending my very heart. I would have been glad to keep him with me, in order that he might serve me on your behalf during my imprisonment for the gospel …

St. Peter, likewise, refers to “my son Mark” (1 Peter 5:13). The Protestant Jamieson-Fausset-Brown Bible Commentary notes about this passage:

Papias reports from the presbyter John [Eusebius, Ecclesiastical History, 3.39], that Mark was [the] interpreter of Peter, recording in his Gospel the facts related to him by Peter. … That Mark had a spiritual connection with the Asiatic churches which Peter addresses, and so naturally salutes them, appears from 2 Timothy 4:11; Colossians 4:10.

Another work, the Cambridge Bible for Schools and Colleges, also states regarding 1 Peter 5:13:

It is natural, in the absence of any evidence to the contrary, to assume that the Marcus so named is identical with the “John whose surname was Mark,” the son of the Mary to whose house St Peter went on his release from imprisonment (Acts 12:12), the cousin of Barnabas (Colossians 4:10), the companion of St Paul on his first missionary journey (Acts 13:5). On this assumption the term “son” might be used of him either as implying the spiritual parentage of conversion, or as the expression of an affection like that which St Paul cherished for Timotheus (1 Timothy 1:2) and Titus (Titus 1:4).

St. John thinks in the same way about spiritual fatherhood:

3 John 1:1-4 The elder to the beloved Gaius, whom I love in the truth. Beloved, I pray that all may go well with you and that you may be in health; I know that it is well with your soul. For I greatly rejoiced when some of the brethren arrived and testified to the truth of your life, as indeed you do follow the truth. No greater joy can I have than this, to hear that my children follow the truth.

The same word (pater) in the Septuagint (the third century BC Greek translation of the Bible) was used by the prophet Elisha in addressing the prophet Elijah, when the latter went up to heaven in a fiery chariot: “My father, my father!” (2 Kings 2:12), and one of the kings of Israel called Elisha “My father” (2 Kings 6:21).

Perhaps the most “papal” use of pater in the Septuagint is in Isaiah 22:21 (“he shall be a father to the inhabitants of Jerusalem”). It’s all the more interesting because it’s part of a passage that Jesus clearly had in mind when giving St. Peter the “keys of the kingdom” (Matthew 16:19).