After being arrested in Jerusalem at the instigation of the Jews who abhorred Paul for his ministry to the Gentiles, he spent two years in prison in Caesarea before appealing to Caesar and going to Rome.  There he spent two more years under house arrest while awaiting his trial before the emperor (see Acts 28:30).  During this time he wrote what have been called his four prison epistles: Ephesians, Philippians, Colossians and Philemon.  Of these, Philippians appears to have been written last toward the end of his imprisonment (approx. 62 a.d.) when he was expecting his release (see Phil 1:25-26, 2:24).  The Philippians were among his most faithful supporters:  After establishing the church on his second missionary journey (Acts 16:9-40) they had sent a gift “more than once” for his needs while ministering in Thessalonica (Phil 4:15-16).  On his third missionary journey he traveled through Macedonia (of which Philippi was the capital) both on his way to and from Greece rather than taking the more direct sea voyage across the Aegean from Ephesus (Acts 19:21,22, 20:1-3,6, 1 Cor 16:5-7).  Now, having learned of his Roman imprisonment, they had sent Epaphroditus as well as a monetary gift to assist the apostle in his affliction (Phil 2:25, 4:18).  Recalling his unjust prison experience in Macedonia and the testimony of the Philippian jailer himself (Acts 16:25-40) they were quick to overlook the stigma of the apostle’s imprisonment and continue their faithful support of him.  Paul rejoiced at their revived concern for him and wrote to express his gratitude.  At the same time he also wanted to warn the believers there against those of the “false circumcision” (Phil 3:2) who stood opposed to the truth of the gospel and were responsible for his imprisonment.  Epaphroditus had also related some minor disagreements that had arisen among the Philippians that Paul wished them to overcome in the spirit of Christian humility.  Finally, during his visit Epaphroditus had become deathly sick, so that the Philippians were concerned when they heard of his illness, and Epaphroditus himself was distressed because of their concern.  Thus Paul, ever mindful against being a burden to anyone (2 Cor 11:9, 12:13-16, 1 Thess 2:9, 2 Thess 3:8), was anxious to send him back to the Philippians in order that they might rejoice and he might be relieved of the anxiety of the situation (Phil 2:25-28).