A warm bond of love existed between Paul and the Christians in Philippi. They had sent funds to Paul a number of times. (2Co 11:9; Php 4:10, 14-16) In this letter, Paul refers to them as his “beloved ones,” and though he longs for his heavenly reward, he is determined to remain in the flesh for their sakes. (Php 1:8, 24; 2:12; 4:1) Paul does not have to present strong arguments and reproofs in this letter as he did, for example, in his letters to the congregations in Corinth and Galatia. To the Philippians, he gives loving encouragement.

Joy is a major theme of this letter. Despite his tribulations, Paul is joyful over the advancement of the good news, and he urges the Philippian Christians to rejoice.​—Php 1:18; 2:17, 18, 28, 29; 4:1, 4, 10.

Paul also wrote (1) to thank the Philippians for the gifts they had sent (Php 4:10-18); (2) to explain why he sent Epaphroditus back so that they would not draw wrong conclusions (Php 2:25, 26); (3) to inform them about his own situation in Rome (Php 1:12-26); (4) to admonish them to be united (Php 2:1, 2; 4:2); and (5) to warn them against false teachings (Php 3:1–4:1).

Many fine principles expressed in this letter provide guidance and encouragement to all Christians:

• Make sure of the more important things, and do not stumble others.​—Php 1:9-11.

• Be humble in imitation of Christ; doing so brings exaltation from God.​—Php 2:5-11.

• Keep making progress as a Christian, and continue walking orderly in this same course.​—Php 3:16.

• Minimize anxiety in all situations by supplicating God, who gives peace that guards the heart and mental powers.​—Php 4:6, 7.

In this letter, Paul does not quote directly from the Hebrew Scriptures, but he apparently alludes to a number of scriptures.​—Compare, for example, Php 2:15 with De 32:5; Php 3:1; 4:4 with Ps 32:11; 97:12; Php 4:5 with Ps 145:18.

Internal evidence indicates that this letter was written during Paul’s first imprisonment in Rome. He says that the reason for his being in bonds was known among “all the Praetorian Guard,” and he sends greetings from “those of the household of Caesar.” (Php 1:7, 13, 14; 4:22; Ac 28:30, 31) Paul’s first imprisonment in Rome is generally considered to have taken place about 59-61 C.E. He very likely wrote this letter about 60 or 61 C.E., a year or more after his arrival in Rome. There had been time for Epaphroditus to come from Philippi, about 1,000 kilometers (600 mi) away, with a gift for Paul. There had also been time for news of Epaphroditus’ illness in Rome to get back to Philippi and for expressions of sorrow over this news to come from Philippi to Rome.​—Php 2:25-30; 4:18.

An abundance of evidence shows that Paul was the writer of this letter. Polycarp (69?-155? C.E.) in his own letter to the Philippians mentions that Paul had written to them. Such early Bible commentators as Clement of Alexandria, Ignatius, Irenaeus, and Tertullian quote the letter to the Philippians as being from Paul. Philippians is cited in the Muratorian Fragment of the second century C.E. and in all other early canons. It appears side by side with eight other letters of Paul in the papyrus codex referred to as P⁴⁶ (Papyrus Chester Beatty 2), believed to date from about 200 C.E.