© Getty Images

Roads -

The spread of Christianity owes a lot to Roman roads. The network of roads sweeping across the vast empire allowed for early Christian leaders such as Paul the Apostle to travel and share the Gospel.

© Getty Images

Roads -

The Christian message of hope was particularly appealing to those experiencing social problems, including poverty, and these roads allowed it to reach large metropolises.

© Getty Images

Christians didn't call themselves Christians -

There is no mention in the Bible of Jesus referring to his followers as "Christians." Instead, those who followed Christ called themselves "saints" or members of "The Way."

© Getty Images

Christians didn't call themselves Christians -

"Saints" comes from the Greek hagios, which means "holy," or "sacred." "The Way" is a reference to the Hebrew concept of halakhah, which comprises a set of rules by which Jews should live by.

© Getty Images

But then they started to call themselves Christians -

It's not until Acts 11:26 that we find a reference to "Christians," when the leaders at Antioch use it to describe the followers of Christ. It reads: "[...] The disciples were called Christians first at Antioch."

© Getty Images

Early Christians relaxed the rules -

Jesus was a Jew who taught mostly to Jewish people, but an audience of gentiles (non-Jewish people) started to follow his teachings as well.

© Getty Images

Early Christians relaxed the rules -

Coming from a pagan background, many didn't follow Jewish principles, and things such as dietary restrictions were not followed.

© Getty Images

Early Christians relaxed the rules -

In addition, gentile males were also not circumcised. These and other Jewish rules and traditions became relaxed as early Christianity took form and more and more gentiles joined the movement.

© Getty Images

Persecution came in waves -

The persecution of Christians in ancient Rome came in waves. Indeed, 12 of the 54 Roman emperors who ruled between 30 CE and 311 CE persecuted Christians, with Emperor Nero (pictured) taking the trophy as the most ruthless.

© Getty Images

Persecution came in waves -

Nero used Christians as a scapegoat for the Great Fire of Rome, and they paid for it with their lives in atrocious ways.

© Getty Images

Persecution came in waves -

Christians were persecuted, crucified, burned alive, and literally thrown to the lions for centuries. This, of course, until Emperor Constantine converted to Christianity and ended the persecution in 312 CE.

© Getty Images

They didn't go to physical churches -

In the early days, there was no such thing as physical Christian churches. Groups would gather for worship in each other's homes.

© Getty Images

They didn't go to physical churches -

An example can be found in Romans 16:3-5, where Paul the Apostle makes reference to meetings held in the house of a couple, Priscilla and Aquilla.

© Shutterstock

Communities -

Being a Christian back then meant being an outcast. They would organize themselves in close-knit communities where both Jews and gentiles mixed as followers of Christ.

© Getty Images

Communities -

They would dedicate themselves to helping the poor and those in need, as well as studying and worshiping. Early Christians redefined what it was to have a sense of community in ancient Rome.

© Getty Images

Though some felt like second-class citizens -

While gentiles made up a considerable part of early Christians, they still felt somehow like second-class citizens amongst Jewish followers.

© Getty Images

Second-class citizens -

This was particularly accentuated when Peter the Apostle succumbed to the pressure of religious leaders and started to distance himself from gentiles—an action that was condemned by Paul the Apostle.

© Getty Images

Paul's response to Peter's actions -

Galatians 2:11-13 reads: "When Cephas came to Antioch, I opposed him to his face, because he stood condemned. For before certain men came from James, he used to eat with the Gentiles. But when they arrived, he began to draw back and separate himself from the Gentiles because he was afraid of those who belonged to the circumcision group. The other Jews joined him in his hypocrisy, so that by their hypocrisy even Barnabas was led astray."

© Getty Images

They might just die sooner than expected -

It was not easy being a Christian in ancient Rome, particularly during the days of persecution. Martyrdom was just around the corner for many of them.

Famous Christian martyrs include Paul the Apostle, who was beheaded, and Peter the Apostle, who was infamously crucified upside down in Rome.

© Getty Images

They might just die sooner than expected -

Others might not have gotten their names mentioned in the Bible or in any other books, but nonetheless lost their lives for being followers of Christ.

© Getty Images

Religious arguments were confusing -

Christ was not around for a long time and had quite a sudden, tragic death, so there was some debate over a number of things. This included the concepts of "low Christology" and "high Christology."

© Getty Images

Religious arguments were confusing -

In a nutshell, "low Christology" defended that Jesus was a human, except he had no sin.

© Getty Images

Religious arguments were confusing -

On the other hand, "high Christology" argued that Jesus was part of the Holy Trinity, and therefore divine.

© Getty Images

The relationship between Jews and Christians -

Jesus challenged and argued with numerous Jewish leaders in his day.  But despite early tensions, Jews and Christians coexisted peacefully for the most part during the Roman Empire.

© Getty Images

They could be thrown in the gladiatorial arena -

Emperor Septimius Severus started torturing and killing Christians in the gladiatorial arena for entertainment around 192 CE.

© Getty Images

They could be thrown in the gladiatorial arena -

By 202 CE, Romans were forbidden to convert to Judaism or Christianity. Those who defied the Emperor ended up being attacked by wild animals, beheaded, and burned, among other punishments.

© Getty Images

The legalization of Christianity brought new problems -

Christianity was recognized legally in 313 CE, when Emperor Constantine issued the Edict of Milan.

© Getty Images

The legalization of Christianity brought new problems -

While this was great news for Christians in general, who no longer would be persecuted, it brought new problems as to how the religion would be organized and which set of rules would be adopted.

© Getty Images

The legalization of Christianity brought new problems -

This then led to some Christian groups being ostracized, some of whom were even considered heretics and lost their legal status.

Sources: (Grunge)

See also: Famous Christian symbols explained

© Getty Images