ἄλισγμα (alisgēma) appears once in the Greek New Testament, in Acts 15:20, as the plural ἀλισγημάτων. The term denotes pollutions or defilements associated with idolatrous worship.

Context within the Jerusalem Council

Acts 15 records the first church council, convened in Jerusalem to address the inclusion of uncircumcised Gentile believers. After hearing testimony from Paul, Barnabas, and Peter, James offers the decisive proposal:

“…that we should write to them to abstain from the pollutions of idols, sexual immorality, from what has been strangled, and from blood.” (Acts 15:20)

Here ἀλισγημάτων specifies the first of four prohibitions. The council is not imposing a modified Mosaic Law upon Gentiles; instead, it safeguards table fellowship and discipleship between Jewish and Gentile believers by removing practices most offensive to Jewish conscience (cf. Acts 15:21).

Defilement in the Old Testament Background

The idea of “pollutions” or ritual defilement permeates the Torah. Exodus, Leviticus, and Deuteronomy describe idolatry as the highest affront to covenant holiness. Idols are often labeled “abominations” (e.g., Deuteronomy 29:17). The Septuagint uses cognate terms to translate Hebrew טָמֵא (tameʾ, “unclean”) and שִׁקּוּץ (shiqqûṣ, “detestable thing”), linking idolatry with defilement of persons, land, and sanctuary (Leviticus 18:24–28; Ezekiel 20:7). Acts 15:20 draws upon this heritage: Gentile believers must renounce idolatrous contamination if they are to share life and worship with Jewish Christians grounded in the holiness code.

Idolatrous Pollutions and Gentile Conversion

First–century Gentiles commonly participated in civic feasts dedicated to local deities. Meat sacrificed to idols was served in temple precincts and private homes alike (1 Corinthians 8:10). Accepting Christ required a decisive break from this milieu (1 Thessalonians 1:9). The council’s ruling, therefore, establishes a baseline of repentance:
• No participation in idol temples or sacrificial meals (cf. 1 Corinthians 10:14–22).
• Avoidance of any social practice that advertises allegiance to false gods (Revelation 2:14, Revelation 2:20).

By grouping ἀλισγήματα with sexual immorality and blood regulations, the letter underscores that idolatry defiles both body and community.

Theological Implications for Holiness

1. Sanctity of worship: Only the living God deserves sacrifice and fellowship (Romans 12:1).
2. Sanctity of the body: Idolatry often involved sexual rites; thus moral purity is inseparable from right worship (1 Corinthians 6:15–20).
3. Sanctity of the table: Food offered to idols renders shared meals spiritually dangerous; abstention preserves unity (Romans 14:15–20).

Implications for Church Fellowship and Unity

The fourfold decree functions pastorally:
• It protects Jewish believers from ritual contamination (cf. Daniel 1:8).
• It prevents Gentile believers from reverting to pagan customs.
• It forges a common ethic that transcends ethnicity (Ephesians 2:14–16).

Luke’s narrative shows the result: “So the churches were strengthened in the faith and grew daily in number.” (Acts 16:5)

Continuing Relevance for Christian Ethics and Mission

Modern idols—materialism, nationalism, entertainment, and self—still produce ἀλισγήματα, corrupting heart and witness. Contemporary application involves:
• Renouncing any loyalty that rivals Christ (Matthew 6:24).
• Exercising liberty with regard for weaker consciences (1 Corinthians 8:9).
• Maintaining gospel clarity in pluralistic cultures (1 John 5:21).

By obeying the spirit of Acts 15:20, believers bear a distinctive holiness that commends the gospel to the nations and preserves the unity for which Jesus prayed (John 17:21).