Jail-Based Ministry
The Apostle Paul spent a surprising amount of his 35-year ministry (33 to 68 A.D.) in prison or as a prisoner. His first imprisonment was in Philippi where he only spent a brief time in jail (Acts 16).
Paul's second stint in prison, by far his longest, lasted from his early 58 A.D. arrest in Jerusalem (Acts 21) to his early 63 A.D. acquittal in Rome. His final time in prison, lasting roughly four to six months, took place just before his martyrdom in May or June of 68 A.D.
Apostle Paul spent at least five and one-quarter years of his ministry as a prisoner. He was wrongly arrested and placed in prison just like he had zealous done to Jewish Christians before his conversion (Acts 8:3, 22:4, 26:9 - 10). He received this type of treatment as part of the suffering he was prophesied to endure for the sake of the gospel (Acts 9:15).

The First Imprisonment
Apostle Paul's first taste of prison as a Christian came during his second missionary journey (Acts 16). Two slave masters in Philippi become angered at Paul after he casts out a money-making demon from their female slave. They stir up the city against him and Silas, leading to them being beaten and thrown in jail! Their stay, however, is short lived as a miraculous earthquake sets them free.
Relatives in Prison!
The book of Romans, written late in 57 A.D. from Corinth, mentions two people who were fellow prisoners with Paul.
Salute Andronicus and Junia, my kinsmen and my fellow prisoners, who are of note among the apostles, who also were in Christ before me (Romans 16:7, HBFV throughout).
Andronicus and Junia were not only (likely) husband and wife, but evidence also suggests they were distant relatives of Paul living in Rome (see our article on Paul's relatives)! It is unclear, however, exactly when or where they shared a prison with their famous apostolic kinsman.
Caesarea
In May of 58 A.D. Paul is arrested by the Romans after he is suspected of causing a riot at Jerusalem's temple. He is eventually escorted, protected by 200 Roman soldiers, to Caesarea where his case would be heard. He is placed in prison upon his arrival and allowed visitors.
And he (Roman Governor Felix) ordered the centurion to keep Paul, to let him have liberty, and not to forbid those of his own to come to him or to minister to him (Acts 24:23).
Paul's stay in a Caesarea prison runs from early summer of 58 A.D. to early autumn of 60. During this time Luke, who had accompanied the apostle on his third missionary journey just prior to his arrest, often visited him in prison.
"During Paul's Caesarean protective custody (58 - 60 AD), Luke had free access to Paul. It was during this time that Luke must have written his Gospel account and compiled nearly all of the information for the book of Acts.
"Jerusalem was not far from Caesarea, and it would have been easy for Luke to go to Jerusalem, where the eyewitness records of Jesus' ministry must have been kept." (Holy Bible, a Faithful Version, second edition, page 51).
Transported for Trial
Paul's Caesarea prison incarceration ends when his request for his case to be heard by Caesar in Rome in granted (Acts 25:12). Accompanying him on the long journey are Luke and Aristarchus.
Now when it was decided that we should sail to Italy, they delivered up Paul and certain other prisoners to a centurion named Julius, who was of the band of Augustus.
And after boarding a ship of Adramyttium that was about to pass by the coasts of Asia, we set sail; and Aristarchus, a Macedonian of Thessalonica, was with us (Acts 27:1 - 2).
An Evangelist in Chains
Paul's "prison epistles," written in Rome between the early spring of 61 A.D. to the early spring of 63, reveal who visited him while he awaited his trial. Ephesians tells us that Tychicus (Ephesians 6:21) paid him a visit. The book of Philippians records Timothy (Philippians 1:1) and Epaphroditus (4:18) also came to him in the Roman capital.
Colossians 1:7 states Epaphras visited Paul in prison as did Onesimus (4:9), the gospel writer Mark (4:10), and Jesus (also called Justus, 4:11). Aristarchus, Luke and Demas are also confirmed as visiting him (4:10, 14). The book of Philemon merely repeats some of those already mentioned in Colossians who were with the apostle.
Paul almost certainly received more prison visitors for this period, other than what the Bible records, as he was allowed the freedom to have as many as he wanted.
And Paul remained two whole years in his own hired house, welcoming all who came to him, proclaiming the kingdom of God, and teaching the things concerning the Lord Jesus Christ with all boldness, no man forbidding him (Acts 28:30 - 31).
Prisoners or Helpers?
There is a bit of a mystery surrounding two of the men who were with Paul during his first time in a Roman prison.
In Colossians Aristarchus is called a fellow prisoner (Colossian 4:10) while Epaphras is referenced as a fellow servant (1:7). In Philemon, however, Aristarchus is labeled a fellow worker (Philemon 1:24) while Epaphras is called a fellow prisoner (1:23)!
Biblical commentaries are split concerning the status of Aristarchus and Epaphras. Some say they were Roman prisoners like Paul. Others, however, state they were some of the many who traveled with or to the apostle to aid his ministry like Luke or Mark. They argue that the reference to a prisoner in Colossians 4:10 and Philemon 1:23 should be taken in a figurative sense.
Biblestudy.org favors the belief that both men, likely during different periods between 61 and 63 A.D., were placed in prison with Paul. This would not be unusual at the time, as Christianity's spread was not only well known but also widely spoken against (Acts 28:21 - 22).
"As Aristarchus had been a zealous and affectionate adherent to St. Paul, and followed him in all his journeys, ministering to him in prison, and assisting him in preaching the Gospel in Rome, he might have been imprisoned on this account" (Adam Clarke's Commentary).
The Second Roman Imprisonment
Paul is acquitted of the charges against him and released from prison in the spring of 63 A.D. He then spends the next few years evangelizing places like Spain and possibly Britain. He is arrested yet again and sent back to Rome in early 68.
The book of 2Timothy, the last one Paul will write, was written when the apostle was in prison in Rome awaiting his inevitable demise. Those who had contact with him during this time include Demas, Crescens, Titus, Luke and Tychicus (2Timothy 4:10 - 12). Those who also visited him include Eubulus, Pudens, Linus, Claudia and other brethren living in Rome (verse 21).
Timothy and Mark can be added to the list of visitors during this last jail term if they were able to get to Rome before the apostle's martyrdom in May or June of 68 A.D. (see 2Timothy 4:9, 11, 21).
Conclusion
Apostle Paul had quite a few people visit and help him during his times in prison. These included two gospel writers (Mark and Luke), his best friend Timothy, Titus, Onesimus and many others. Fellow Christians such as Silas, Aristarchus and Epaphras were jailed with him as well as his converted relatives Andronicus and Junia.
Remarkably, the Bible hints that Apostle Paul was a prisoner far more often, and therefore had even more prison visitors, than what it records!
Are they servants of Christ? (I am speaking as if I were out of my mind.) So am I (Paul), above and beyond measure - in labors more abundant, in stripes above measure, in imprisonments more frequent . . . (2Corinthians 11:23, see also 6:4 - 5).