Most of us know a bit about first-century Christianity, since we’re probably familiar with the writings of the New Testament. The Acts of the Apostles and Paul’s letters, for example, show a fledgling church confronting its first challenges and controversies—all the while giving us a peak at early Christian beliefs and practices. But what happened after the Apostles left the scene?
Actually, we know a good deal about the second-century church thanks to a group of Christians known as the Apostolic Fathers. These guys were disciples of the Apostles, learning from them and even succeeding them in roles of leadership. They provide an important link to the first-century church, as they show how the baton of faith was passed on from Christ’s first disciples to the next generation of Christians.
This blog post was formed from the testimony of several early Christians, but of special mention are these Apostolic Fathers who personally knew the Apostles. Clement of Rome knew both Paul and Peter and succeeded the latter as third bishop of Rome. Ignatius, bishop of Antioch, learned from John and took responsibility for the church in Antioch after Peter had left. Polycarp of Smyrna, friend of Ignatius, also knew John and was an important leader in Asia Minor (modern-day Turkey). These Christians are, in turn, connected to later second-century Christians mentioned in this post. Because of such continuity, these early figures give us exceptional insight into how early Christians understood Christ’s teachings as proclaimed by the Apostles.
Below are 5 highlights from second-century Christianity. By appreciating the witness of this early period, perhaps we can better configure our own faith to that of the early church—in hopes of being more faithful to Christ and his Apostles.
1. A distinctive lifestyle
By the second century, Christianity had distinguished itself from Judaism, becoming a largely Gentile movement as the faith shifted to major cities like Rome, Antioch, and Alexandria. The new movement also set itself apart from the surrounding paganism of the Roman Empire, which was often at odds with the Christian way of life. A distinctively Christian ethic developed as believers took up a radical lifestyle that greatly contrasted with the rest of society.
The Church was both a great equalizer and gathering force, made up of all ranks and races of people. The second-century convert Justin Martyr says that while they had previously “hated and destroyed one another,” Christians are now accustomed to living “with men of a different tribe.”1 At a time when slavery was rampant in Roman society, slaves could be accepted as equals in the faith—even becoming bishop, like Clement of Rome. Second-century Christians were community-oriented. They tended to the needs of their fellow Christians, holding a “common stock” in order to “share with everyone in need.”2 Initially, Christians met privately in homes, for they couldn’t build churches until persecution had ceased. There they celebrated the Eucharist (discussed below), which was sometimes combined with a larger meal known as the Agape. They also read the scriptures, though there would not be an official Bible until the fourth century. While the four Gospels were accepted early on, Christians disagreed about other writings, like Revelation, and included others, like Clement’s Letter to the Corinthians.
Baptism marked entry into the Church, whereby a convert was both “born again” and “regenerated” by “washing away the sins of [one’s] early blindness.”3 Because Baptism demanded a new way of life, new converts would endure a period of reflection, prayer, and fasting beforehand. When describing this distinctly Christian way of life, early Christians referenced Christ’s teachings from the Gospels, especially the Sermon on the Mount. The first-century Didache begins with the radical call to love one’s enemy. “Bless those who curse you,” it says, “and pray for your enemies”—obvious references to Christ’s own words.4 The Didache also reaffirms the two greatest commandments—loving God and loving neighbor. “The height to which love exalts is unspeakable,” says Clement, bishop of Rome.5 Essential to the Christian life was chastity, a virtue not widely embraced in Roman society. While this meant rejecting unchaste practices, as with the Didache’s condemnation of fornication, pederasty, and adultery, it also meant upholding chastity as a good in its own right. Justin Martyr was proud to know of many men and women who had remained “pure” even into old age.6 Above all, these Christians were emphatic about Christ’s lordship and denied interest in a merely human kingdom. “All the kingdoms of this earth,” declared Ignatius of Antioch, “shall profit me nothing.”7
2. Perseverance during persecution
In the second century, becoming Christian meant risking one’s life, as Christianity was not legalized by the Roman Empire until the year 313. During this span of nearly 300 years, thousands of Christians were put to death. Both church leaders and ordinary believers boldly professed Christ until the end—even when they could have saved their lives by renouncing the faith. Such suffering was met with celebration, though, as Christians upheld these martyrs as witnesses to Christ and participants in his own passion and death.
As suggested above, the Christian way of life was radically different from the rest of Roman society—and noticeably so. Christians were accused of being subversive because they rejected imperial institutions like emperor worship. Because their commitment to Christ was incompatible with loyalty to the empire, Christians were seen as enemies of the state. Not only Roman officials but local populations went after Christians, who served as scapegoats for their anger and fear. Christians were blamed for natural calamities because of their rejection of pagan gods. The North African convert Tertullian remarked that if there was “an eclipse, or earthquake, or famine, or plague,” then people were quick to cry “Christians to the lions!”8
Ironically, far from exterminating Christianity, martyrdom strengthened it. Tertullian famously said that “the blood of the martyrs is the seed of the Church.”9 Indeed, martyrs both encouraged believers and converted non-believers by their supreme act of faith in and love for Christ. Many of the Christians mentioned in this blog post were martyred—and they’ve been remembered for nearly two millennia in what has become the world’s largest religion. Around the year 107, Ignatius, bishop of Antioch in Syria, was arrested and taken to Rome, where he was fed to lions in the Coliseum. Along the way, he wrote seven letters expressing his desire to die for Christ. He begged the Roman church not to intervene. No, he was “eager to die” so as to be an “imitator of the passion” of Christ.10 One of Ignatius’ letters was addressed to Polycarp, bishop of Smyrna in Asia Minor, who also met a martyrs death. Polycarp was a prime catch, for he was the chief Christian leader of the entire region. After returning from Rome to discuss the date of Easter, he was soon arrested, tied to a stake, and burned alive—though he was ultimately stabbed for the flames would not touch him. Justin Martyr, whose very writings were meant to persuade the Roman Empire to cease their persecutions, was beheaded along with six other Christians. These men and countless others would be regarded as the holiest of Christians—as models of the faith, as saints. As the Martyrdom of Polycarp testifies, already in the second century Christians are gathering the relics of the deceased and celebrating their feast days (usually the day of their martyrdom).11
3. The Church, both one and universal
In a time when both competing sects and internal divisions were already threatening the unity of the Church, second-century Christians emphasized the oneness and universality of the Church. For them, the unity of the church did not refer to some vague spiritual union of believers. That Christ founded one church meant the existence of a recognizable, visible body of believers scattered across the world.
In the second century as it was in the first, keeping Christ’s flock together was of paramount importance. Because of this, being Christian was not simply a matter of assembling “together in any place whatsoever.”12 No, second-century Christians abhorred division in the Church. Departing from the “primitive succession” of bishops was one of the worst things one could do, since that meant severing continuity with the Apostles—and, ultimately, the Church.13 If anyone enters into schism, says Ignatius of Antioch, “he shall not inherit the Kingdom of God.”14a In the third century, Cyprian, bishop of Carthage, would staunchly reiterate such a warning in his Unity of the Church, warning that one “who forsakes the Church of Christ,” will forfeit the “rewards of Christ.”14b Towards the end of the first century, Clement of Rome wrote a powerful letter to the church in Corinth in order to address an internal sedition taking place. The letter encouraged the Corinthian troublemakers to seek reconciliation with the church. Fortunately, the problem was settled, and the Corinthians celebrated the bishop’s letter for decades to come.
For these Christians, the oneness of the Church went hand in hand with its global presence. Ignatius of Antioch was the first writer to call the Church catholic, meaning universal, in which he relates union with the bishop to union with the universal Church.15 From this time on, “Catholic Church” would increasingly be used to distinguish the global Church from other sects. And how did one know if he belonged to this Church? Again, belonging to an apostolic church—one founded by an Apostle or one of his associates—was crucial. According to Tertullian, the apostolic foundation of the churches really amounts to there being “one primitive Church.”16 Similarly, Irenaeus of Lyons says that the bishops hand on “the Church which is found everywhere.”17 A chief player for the Church’s unity was the bishop of Rome—the one who occupied the “single chair” of Peter, the leader of the Apostles.18 “A primacy is given to Peter,” says Cyprian, “whereby it is made clear that there is but one Church and one chair.”19 According to Cyprian, this so-called “chair” of Peter is the fount of the entire Church’s unity. Because of this understanding, Cyprian seriously doubts that someone who “deserts the chair of Peter” still remains in the Church.20
4. The importance of the bishop
Second-century Christians stressed the office of bishop, whom they regarded as the shepherd and teacher of a local Christian community. The Apostles appointed the first bishops to succeed them in their ministry of overseeing the Church. As a result, Christians understood the bishop—along with his co-workers, the presbyters (or priests)—to be the center of unity for the local church.
Ignatius of Antioch, who himself was bishop of that city, declares the necessity of doing “nothing without the bishop.”21 Throughout his letters, Ignatius singles out the bishop as the go-to source for orthodoxy and means of Christian unity. When new sects began to appear, Christians needed to determine what was, in fact, authentic teaching. Above all else, continuity with the Apostles was key. In his second-century work Against Heresies, Irenaeus of Lyons refuted Gnostic sects by showing how their leaders have no apostolic foundation. Gnosticism, after all, also claimed to be Christian. But unlike them, the authentic Christian churches are able to list their apostolic founders and the bishops who have since succeeded them. The late second-century Christian Tertullian said that sects must simply “unfold the roll of their bishops” in order to defend their novel claims—an endeavor likely to fail.22
At this time, we also see Christians identify the bishop of Rome (i.e., the pope) as the exemplar of orthodoxy. The Apostles Peter and Paul ended their ministry in Rome in the late 60s, when they were martyred. Because of this, Rome had an exceptional apostolic pedigree. After all, Peter was the “preeminent” and “first among the disciples.”23 And just as Peter was shepherd of the early Christian community, so the successors of Peter in Rome would continue this role in the Church. Irenaeus points to the church of Rome as the preeminent model of apostolic teaching, declaring that “the faithful in the whole world” must agree with it due to its “superior origin.”24 As suggested even earlier by Clement of Rome’s letter to the Corinthians, Christians increasingly saw Rome as having a special pastoral role among the churches. A few years after Clement, Ignatius of Antioch would praise the Roman church as “presiding in love.”25
5. The centrality of the Eucharist
In the second century, the celebration of the Eucharist, or Lord’s Supper, was the chief expression of Christian worship. After all, for these Christians, consuming the Eucharist meant partaking of the actual body and blood of Christ and participating in the sacrifice of the New Covenant. In fact, at this time, the belief in the real presence can be found throughout the Church—from Syria to North Africa on up to Rome and modern-day France.
The classic testimony comes from Justin Martyr, a philosopher-turned-Christian who was one of the first major apologists, defending the faith from both Jewish and Roman misunderstandings. In his First Apology, Justin clarifies the practice of the Eucharist, which pagan Romans had misconstrued to be—get this!—cannibalism. He explains how Christian worship is divided into two main parts: the reading of scripture and the celebration of bread and wine—the basic structure that would undergird liturgies throughout the Christian world. Justin is clear that the Eucharist is not mere “common bread or common drink”—no, it is the “flesh and blood of that Jesus who became incarnate.”26 Irenaeus of Lyons agrees. Because it is the “body and blood of the Lord,” the Eucharist offers us the “gift of God, which is eternal life.”27 Eighty years earlier, Ignatius of Antioch would criticize the Gnostics because they did not believe that the Eucharist is truly Christ’s flesh, the same “flesh which suffered for our sins.”28
Besides Christ’s presence, second-century Christians also regarded the Eucharist in terms of sacrifice. For them, the Eucharist was the “sacrifice of the new covenant,” which had been foreshadowed by the Old Testament sacrifices.29 They loved to reference a prophecy from Malachi, which speaks of a coming age when Gentiles will offer a “pure” sacrifice to God.30 According to Justin Martyr, the predicted Gentiles are Christians “who in every place offer sacrifices” through the “bread” and “cup” of the Eucharist.31 Ignatius of Antioch speaks of “one common Eucharist” offered on “one single altar of sacrifice.”32 Writings from the previous century depict the same understanding. Like Ignatius, Clement of Rome connects the office of bishop with the offering of the Eucharistic sacrifice.33 An earlier document known as the Didache says that Christians are to gather on the Lord’s Day and “offer the Eucharist”—but only after confessing one’s sins, so that one’s sacrifice “may be a pure one.”34
 Justin Martyr, First Apology 14.
 Justin Martyr, First Apology 61.
 Didache 1.
 Clement of Rome, Letter to the Corinthians 49.
 Justin Martyr, First Apology 15.
 Ignatius of Antioch, Epistle to the Romans 6.
 Tertullian, The Apology 40.
 Ignatius of Antioch, Epistle to the Romans 6.
 Martyrdom of Polycarp 10.
 Irenaeus of Lyons, Against Heresies 4:26:2.
[14a] Ignatius of Antioch, Epistle to the Philadelphians 3.
[14b] Cyprian of Carthage, On the Unity of the Church 6.
 Ignatius of Antioch, Letter to the Smyrneans 8:2.
 Tertullian, Demurrer Against the Heretics 20.
 Irenaeus of Lyons, Against Heresies 4:33:8.
 Cyprian of Carthage, On the Unity of the Church 4.
 Ignatius of Antioch, Letter to the Trallians 2.
 Tertullian, Demurrer Against the Heretics 32.
 Clement of Alexandria, Who Is the Rich Man That Is Saved? 21:3–5.
 Irenaeus of Lyons, Against Heresies 3:3:2.
 Ignatius of Antioch, Letter to the Romans 1:1.
 Justin Martyr, First Apology 66.
 Irenaeus of Lyons, Against Heresies 5:2.
 Ignatius of Antioch, Letter to the Smyrnaeans 7:1.
 Irenaeus of Lyons, Against Heresies 4:17:5.
 Malachi 1
 Justin Martyr, Dialogue with Trypho the Jew 41.
 Ignatius of Antioch, Letter to the Philadelphians 4.
 Clement of Rome, Letter to the Corinthians 44:4–5.
 Didache 14.