an adulteress: a wife who betrays her marriage, and by extension a people who betray God
At its plainest this word names an adulteress: a married woman who is unfaithful to her husband. It is the feminine partner to the word for a male adulterer (μοιχός), and it belongs to a small family of words for adultery. In Greek law adultery was defined by the wife's status, so the word carried a sharp social sting: to be called an adulteress was to be publicly shamed as a woman who had broken the bond that defined her.
Long before the New Testament, the Hebrew prophets pictured Israel as God's wife and her idolatry as adultery. When their books were translated into Greek, the translators reached for this exact word (rather than the looser word for a prostitute, πόρνη) precisely because it names the breaking of a marriage bond, not just loose living. By the first century the word had soaked up that prophetic charge, so a reader heard in it the accent of the Bible, not the street.
That is why the New Testament can use it in two very different ways. Only once, in Paul's marriage illustration, does it carry its plain legal sense of an unfaithful wife. The rest of the time it is a prophetic accusation: Jesus brands his contemporaries an "adulterous generation" for demanding proof after all he has shown them, and James cries "You adulteresses!" at a community that has cozied up to the world. In both cases the charge is not sexual sin but betrayed loyalty to God. The feminine word is aimed even at men, casting the whole audience in the role of the unfaithful spouse of a faithful husband.
Nuances
What background stands behind James's cry "You adulteresses!" addressed to a mixed community: the prophetic picture of God's people as his unfaithful wife, or the wisdom warning about the adulterous woman in Proverbs.
- majorityThe address draws on the prophets' marriage metaphor (Hosea, Ezekiel), casting the worldly church as God's faithless bride.; D. J. Moo, The Letter of James (Pillar, 2000), 186-88; D. G. McCartney, James (BECNT, 2009), 210-12; L. T. Johnson, The Letter of James (Anchor Bible, 1995), 279-80
- minorityThe model is Proverbs 30:20, the way of the adulteress, rather than the Hosea and Ezekiel prophetic tradition.; J. J. Schmitt, "You Adulteresses! The Image in James 4:4," Novum Testamentum 28 (1986), 327-37
How to read "eyes full of an adulteress" in 2 Peter 2:14: whether the concrete word keeps its force (the false teachers are forever hunting for an adulteress), whether it stands by figure of speech for the abstract act ("eyes full of adultery"), or whether it echoes a Jewish idiom of committing adultery with the eyes.
- majorityThe concrete word keeps its full force: the false teachers' eyes are always searching for an adulteress, a partner in illicit sex.; R. J. Bauckham, Jude, 2 Peter (WBC, 1983), 266-67; J. H. Neyrey, 2 Peter, Jude (Anchor Bible, 1993), 215-16; J. N. D. Kelly, A Commentary on the Epistles of Peter and of Jude (BNTC, 1969), 341
- minorityThe concrete word stands by figure of speech for the act itself, giving the sense "eyes full of adultery."; BDAG, s.v. μοιχαλίς, sense 1.b (concrete for abstract)
- minorityThe phrase echoes a Jewish idiom of committing adultery with the eyes (compare Job 31:1).; D. J. Moo, 2 Peter, Jude (NIV Application Commentary, 1996), 122-23