κοινός

common, shared, unclean

Definition

The Greek adjective κοινός (koinos) carries two primary meanings in the New Testament. First, it denotes what is 'common' or 'shared,' referring to collective property or mutual participation, as seen in the early church's practice of holding all things in common (Acts 2:44, Acts 4:32). Second, and more distinctively, it is used in a Jewish ritual sense to mean 'profane,' 'unclean,' or 'defiled,' referring to anything that does not meet Levitical purity standards. This usage is prominent in passages about dietary laws and Gentile contact, where Peter declares he has never eaten anything 'common or unclean' (Acts 10:14, Acts 11:8). The Apostle Paul, however, reinterprets this in the Christian context, stating that nothing is unclean in itself, though it may be so to someone with a weak conscience (Romans 14:14).

Biblical Usage

κοινός is used in two distinct contexts. In Acts, it describes the shared possessions of the believing community (Acts 2:44, 4:32). More frequently, it appears in debates over Jewish purity laws, especially in the Gospels and Acts. In Mark 7:2, the Pharisees criticize the disciples for eating with 'common' (unwashed) hands. The Book of Acts uses it repeatedly in the vision of Peter (Acts 10:14, 28; 11:8) to challenge the distinction between clean and unclean, a pivotal moment for Gentile inclusion. Paul uses it once in Romans 14:14 to argue that purity is a matter of personal conviction in Christ.

Etymology

The word κοινός is a native Greek adjective meaning 'common,' 'shared,' or 'public.' It is the root of significant New Testament words like κοινωνία (koinōnia, G2842) meaning 'fellowship' or 'sharing,' and κοινόω (koinoō, G2840) meaning 'to make common' or 'defile.' Its meaning developed from the neutral sense of 'common property' to the Jewish-Greek sense of 'ritually profane,' influenced by the Septuagint's use to translate Hebrew terms for ceremonial uncleanness.

Semantic Range

κοινός is theologically significant as it sits at the crossroads of law, grace, and community. Its 'unclean' sense highlights the boundary-setting function of the Mosaic law, which the visions in Acts 10-11 dramatically overcome, signaling that the gospel breaks down barriers between Jews and Gentiles. Its 'shared' sense defines the radical economic and spiritual unity of the early church. Understanding this word enriches reading by showing how the New Testament redefines purity—from external ritual to internal faith—and redefines community—from exclusive to inclusive, bound by shared life in Christ.

In its Jewish cultural context, 'κοινός' as 'unclean' was a powerful concept. It did not mean physically dirty but ritually defiled, disqualifying a person or object from worship or holy service. Common items or people (especially Gentiles) were considered outside the sphere of holiness. This created a strong social and religious barrier. The New Testament's use of the word, particularly in Acts, directly confronts and reinterprets this cultural understanding in light of the new covenant.

ἀκάθαρτος (akathartos, G169) — Specifically denotes moral or spiritual 'uncleanliness,' often associated with demons or sin. βέβηλος (bebēlos, G952) — Means 'profane' or 'secular,' focusing on what is unhallowed or desecrated. κοινωνία (koinōnia, G2842) — The noun form meaning 'fellowship,' derived from the 'shared' sense of κοινός.

Word Details

Scripture References