The fourth attribute of the Church is ‘apostolicity.’
According to the Greek tradition, salvation involves the transformation of a sinner into the likeness of God; it is to become by grace what Christ is by nature. This perspective of salvation, called theosis or deification, is at the heart of what it means to say the Church is apostolic. As St. Justin puts it, the apostles “were the first god-men by grace.” He continues:
Each of [the apostles] is a Christ repeated; or, to be more exact, a continuation of Christ. Everything in them is theanthropic because everything was received from the God-man.
—The Attributes of the Church
When Orthodox Christians speak of ‘apostolic succession,’ we are speaking not only to a linear succession in ordination from the apostles, but also a continuation in the beliefs and doctrines of the apostolic Church. While other Christian groups might claim apostolic succession from the standpoint of ordination through the centuries, the Orthodox Church has truly maintained both sides of the succession ‘coin’—both their faith and a continuation of ordination from one of the twelve.
The New Testament bears a significant witness to not only the reality but also the importance of the Church being apostolic:
It is clear that the New Testament Church was an apostolic church. Its leadership consisted of the apostles, who were given this authority by Our Lord that included the powers to bind and loose (Mt 16:9; Mt. 18:8), forgive sins (Jn 20:21-23), baptize (Mt 28:18-20), and make disciples (Mt 28:18-20). We see it exhibited in numerous ways throughout the New Testament, including teaching that the Church is built on Christ and his apostles (Eph 2:19-22), deliberating and pronouncing within an episcopal structure about a theological controversy (Acts 15:1-30), proclaiming what constitutes an appropriate reception of true doctrine (1 Cor 15:3-11), rebuking and excommunicating (Acts 5:1-11;Acts 8:14-24; 1 Cor 5; 1 Tim 5:20; 2 Tim 4:2; Titus 1:10-11), judging the adequacy of a believer’s penance or penitent state (2 Cor 2:5-11; 1 Cor 11:27), the ordaining and appointing of ministers (Acts 14:23; I Tim 4:14), choosing successors (Acts 1:20-26), and entrusting the apostolic tradition to the next generation (2 Thess 2:15; I Tim 2:2). —Francis J. Beckwith (Source)
Looking past the ministry of the original apostles themselves, there are bishops, presbyters, and deacons that have been ordained in succession from them. That these clergy, even in our Church today, are ‘continuations of Christ’ is received as self-evident by even the earliest of fathers.
For example, St. Ignatius of Antioch reminds the local church at Ephesus that obedience to the bishop is “obedience to the Lord” (Ephesians 5) and that:
We should look upon the bishop even as we would upon the Lord Himself. —ibid. 6
To the Magnesians, Ignatius writes that true Christians always show respect to the bishop (ch. 4) and that all true Christians are to:
[D]o all things with a divine harmony, while your bishop presides in the place of God, and your presbyters in the place of the assembly of the apostles, along with your deacons, who are most dear to me, and are entrusted with the ministry of Jesus Christ.
In all of his letters, St. Ignatius characterizes the deacons, priests, and bishops of each local church as continuations of Christ, entrusted with the apostolic deposit. Being a disciple of the beloved John, this teaching came from the apostles themselves.
In his letter to the Corinthians (ca. A.D. 70-90), St. Clement of Rome writes that the apostles:
[A]ppointed their earliest converts, testing them by the Spirit, to be the bishops and deacons of future believers. Nor was this a novelty, for bishops and deacons had been written about a long time earlier . . . and afterwards added the further provision that, if they should die, other approved men should succeed their ministry. —42.4–5; 44.1–3
As with Ignatius’ letters, this was circulating within local churches during the lifetime of some of the twelve apostles.
Eusebius of Caesarea relates the words of Hegesippus (A.D. 180):
When I had come to Rome, I [visited] Anicetus, whose deacon was Eleutherus. And after Anicetus [died], Soter succeeded, and after him Eleutherus. In each succession and in each city there is a continuance of that which is proclaimed by the law, the prophets, and the Lord. —Ecclesiastical History 4.22
In his debates with the Gnostics, St. Irenaeus of Lyons (late-second century) famously writes:
We are in a position to enumerate those who were instituted bishops by the apostles and their successors down to our own times, men who neither knew nor taught anything like what these heretics rave about.
—Against Heresies 3.3.1
For Irenaeus, a way to discern apostolic teaching from that of heretics was to examine the apostolic succession of whoever was teaching something contrary to the rest of the faithful. Rather than arguing back-and-forth with the Gnostics on the basis of scripture alone, it was enough for him to ask: ‘Who is your bishop?’
And what is the apostolic faith? What is that essential deposit of tradition that is handed down in succession from the apostles? St. Justin is plain that apostolic tradition is the person of the God-man, Jesus Christ:
There is but one Truth, one Transcendent Truth: the God-man, the Lord Jesus Christ. Behold, the holy ecumenical councils, from the first to the last, confess, defend, believe, announce, and vigilantly preserve but a single supreme value: the God-man, the Lord Jesus Christ.
As the Church is the fullness (pleroma) of God, to speak of the Church as ‘apostolic’ is to speak of the Church as being indivisibly united to Jesus Christ, through the Holy Spirit, and to the glory of God the Father. The apostolic deposit is Jesus himself—Christ eternal, incarnate, crucified, buried, conquering Hades, resurrected, and reigning eternally:
Apostolic succession, the apostolic heritage, is theanthropic from first to last. What is it that the holy apostles are transmitting to their successors as their heritage? The Lord Christ, the God-man Himself, with all the imperishable riches of His wondrous theanthropic Personality, Christ—the Head of the Church, her sole Head. If it does not transmit that, apostolic succession ceases to be apostolic, and the apostolic Tradition is lost, for there is no longer an apostolic hierarchy and an apostolic Church. —St. Justin Popovich
Apostolic tradition is a ‘continuation of Christ’ through the successors of the apostles because that tradition is Christ himself. And since the heart of apostolic tradition is Jesus Christ—and because he never changes—the heart of apostolic tradition also can never change. As Paul reminds us:
Jesus Christ is the same yesterday, today, and unto ages of ages. Do not be carried away by all sorts of strange teachings. —Heb. 13:8–9
St. Basil similarly writes:
For the tradition that has been given us by the quickening grace must remain for ever inviolate. —On the Holy Spirit
In connecting the changelessness of Christ with an exhortation to not be “carried away” by false doctrine, we see that there is no true Tradition apart from Christ. The apostolic traditions are not “traditions of men,” but are rather traditions of the Holy Spirit (Acts 15:28)—and thus, the terminology holy or sacred tradition.
The Church is living in a new age of the Spirit, promised by the prophets (Joel 2:28–32) and confirmed by the apostle Peter on the first Christian Pentecost (Acts 2:14–21). It is only fitting, then, that our experience as the Church would be marked by a common experience in the Spirit. Rather than confusion—as with the tower of Babel—the Church is characterized by conciliarity, reconciliation, understanding, sobriety, and a unity of faith in the clergy (and laity) who are apostolic continuations of Jesus Christ and defenders of his truth.
Anglican historian J. N. D. Kelley speaks of a “safeguard” in the life of the Church that:
[I]s supplied by the Holy Spirit, for the message committed was to the Church, and the Church is the home of the Spirit. Indeed, the Church’s bishops are . . . Spirit-endowed men who have been vouchsafed an “infallible charism of truth.” —Early Christian Doctrines, p. 37
Since apostolic tradition is both given and preserved by the Holy Spirit, it carries with it—like holy scripture, when interpreted and applied by the Church—the very authority of Christ and his apostles:
Of the beliefs and practices whether generally accepted or publicly enjoined which are preserved in the Church, some we possess derived from written teaching; others we have received, delivered to us in a mystery, by the tradition of the apostles; and both of these, in relation to true religion, have the same force. —St. Basil the Great, On the Holy Spirit
On the apostolicity of the Church, St. Justin concludes:
The personality of the Lord Christ the God-man, transfigured within the Church, immersed in the prayerful, liturgical, and boundless sea of grace, wholly contained in the Eucharist, and wholly in the Church—this is holy Tradition. This authentic good news is confessed by the holy fathers and the holy ecumenical councils. By prayer and piety holy Tradition is preserved from all human demonism and devilish humanism, and in it is preserved the entire Lord Christ, He Who is the eternal Tradition of the Church.
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