This article endeavours to illuminate the socio-economic dimension of Paul's κοινωνία with the Philippians. It initially adduces a representative sample of philological evidence which demonstrates that κοινωνία and its cognates (κοινωνός, κοινωνέω) frequently convey the sense of partnership in some economic enterprise, and establishes a semantic equivalence between κοινωνία and societas (partnership). It is then argued that, from a Roman socio-economic and legal perspective, Paul's κοινωνία consisted of a societas unius rei (i.e. societas evangelii), whereby Paul supplied the ars and opera (skill and labour), while the Philippians contributed the pecunia (funds) to ensure the progress of his mission.

In 1 Cor 10.14–22 Paul warns his readers to refrain from idolatry. In order to convince his readers he calls attention to the unity and solidarity which exist between worshippers of the same religion. In this context he uses the terms κοινωνία and κοινωνός (vv. 16, 18, and 20). In v. 17 Paul tells his readers that at their joint meals they are ‘partners’, this time expressed by the term μετέχειν. In the light of ancient parallels, it is concluded that the references to κοινωνία in v. 16 (cf. vv. 18 and 20) should be understood ecclesiologically, denoting ‘partnership’ rather than ‘participation’.