Proper noun
the Apostolic Age
(Christianity) The period of the Twelve Apostles, dating from the Great Commission of the Apostles by the resurrected Jesus in Jerusalem (c. 33) until the death of the last Apostle, believed to be John the Apostle in Anatolia (c. 100).
In the 290s, Eusebius began work on his magnum opus, the Ecclesiastical History, a narrative history of the Church and Christian community from the Apostolic Age to Eusebius' own time. Source: Internet