Christianity in the 2nd century

Christianity in the 2nd century was largely the time of the Apostolic Fathers who were the students of the apostles of Jesus, though there is some overlap as John the Apostle may have survived into the 2nd century and Clement of Rome is said to have died at the end of the 1st century. While the Christian church was centered in Jerusalem in the 1st century, it became decentralized in the 2nd century. The 2nd century was also the time of several people who were later declared to be major heretics, such as Marcion, Valentinius, and Montanus.

Although the use of the term Christian is attested in the book of Acts from the middle of the 1st century, the earliest recorded use of the term Christianity (Greek: Χριστιανισμός) is by Ignatius of Antioch about 107 AD, who is also associated with modification of the sabbath, promotion of the bishop, and critique of the Judaizers.

At first Christians continued to worship and pray alongside Jewish believers, but within twenty years of Jesus' death, "the Lord's Day" (Sunday) was being regarded as the primary day of meeting and worship among some Christian sects in the city of Rome. Growing tensions soon led to a starker separation that was virtually complete by the time Christians refused to join in the Bar Khokba Jewish revolt of 132, however some groups of Christians retained more elements of Jewish practice. Only Marcion proposed rejection of all Jewish practice, but he was excommunicated in Rome c. 144 and declared heretical by the growing proto-Orthodoxy. Christian communities came to adopt some Jewish practices while rejecting others. Historians debate whether Roman government distinguished between Christians and Jews prior to Emperor Nerva's modification of the Fiscus Judaicus in 96. From then on, practicing Jews paid the tax, and Christians did not. Christianity also differed from other Roman religions in that it set out its beliefs in a clearly defined way, though the process of orthodoxy (right belief) was not underway until the period of the First seven Ecumenical Councils. Most early Christians did not own a copy of the works that later became the Christian Bible or other church works accepted by some but not canonized, such as the writings of the Apostolic Fathers, or other works today called New Testament apocrypha. Similar to Judaism, much of the original church liturgical services functioned as a means of learning these Scriptures, which initially centered around the Septuagint and the Targums.

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