The Apostle Paul utilised three major Greco-Roman urban centres, of the first-century Eastern Mediterranean region of the Roman empire, as his missionary bases. These are Antioch, Ephesus and Corinth.
From Antioch (in the Roman province of Syria), the Apostle Paul launched the first three of his missionary journeys. Ephesus in the Roman province of Asia (today's Turkey), served for about three years as his base in the Anatolian region during his third missionary journey. Corinth on the other hand became Paul's base for his missionary activities in Hellas (the Roman provinces of Achaia and Macedonia), where he stayed for some eighteen months (50-51 AD) during his second journey (Acts 18:11). The "Apostles to the Gentiles" travelled extensively throughout Hellas visiting Philippi, Thessalonica and Beroea in Roman Macedonia, and Athens, Corinth, Cenhrae and Isthmia in Achaia (c.f. Acts of the Apostles and the letters of St. Paul).
There are strategic, spiritual and coincidental reasons why Paul chose Corinth as a base for his work. This essay concentrates on the Providential and spiritual reasons.
One of the key elements in understanding the Apostle Paul is to first understand his profound mystical or spiritual experiences. St. Paul's change in character, for example, was after a mystical experience or vision, as noted in his letter and in St. Luke's account. St Paul was a violent and zealous persecutor of the early Church in Palestine and Syria and, over night, his persecution terminated following his definitive and life-changing "apocalypse of Jesus Christ" (Gal 1:12). This experience occurred along the road leading to Damascus, as explained by St. Luke (Acts 9:1-9). Likewise some of the factors which led to St. Paul's choice of Corinth may be described as Providential or mystical.
Setting off from Antioch with Silas, to revisit the Christian communities which he and St. Barnabas had established in the southern regions of Galatia (today's mid-Turkey, St. Paul had no intension of travelling beyond the parameters of his first missionary journey (c.f. Acts and Galatians). This would therefore include the newly established churches in the various urban centres in south Galatia (since St. Barnabas and St. Mark would visit Cyprus):
The Apostle Paul, furthermore, explains to the north Galatians that he had no design or intent of visiting their region, because he intended to make a second visit to south Galatia:
St. Paul's goal in this planned second missionary journey to south Galatia was simply to convey the decisions reached at the Jerusalem Council. He plans were unexpectedly expanded to include a visit to north Galatia and eventually to Corinth. How did these unplanned journeys occur? Divine Providence played a significant role.
Travelling northward, away from the province of Asia, Paul and his Apostolic circle wandered into north Galatia: "Now when they had gone through Phrygia and the region of Galatia, they were forbidden by the Holy Spirit to preach the word in Asia" (Acts 16:6). At some point St. Paul decided to move north of Asia towards the Aegean coast. But again his movements were guided by divine intervention:
Having arrived at Alexandrian Troas, very close to the site of Homeric Ilium, that is at the northeastern limits of Anatolia (Acts 16:9), the Paul must have wondered whether to return to Antioch or else cross the Aegean Sea to Hellas. The Lucan record explains that the decision was made for him through a visionary or mystical experience:
Having travelled throughout Macedonia preaching the Gospel and establishing churches in Philippi, Thessalonica, Beroae and Athens, St. Paul eventually arrived in Corinth. However, after an initial peaceful stay, he began to encounter some forceful opposition. He must have often struggled with the decision to stay or to leave Corinth. Again by Divine Providence the dilemma was solved for him. In a mystical Christophanic experience, he was encouraged to remain in Corinth:
As a direct consequence of this divine vision, the Apostle made Corinth his missionary base; "And he stayed a year and six months, teaching the word of God among them" (Acts 18:11).
When he first planned his second missionary journey, the Apostle Paul had no intention of travelling beyond south Galatia and Cyprus. By divine vision and intervention however he eventually found himself in Hellas, preaching the Word and making Corinth his missionary base.
"Man proposes, God disposes".
from Voice of Orthodoxy, v. 17-8