to be mismatched in harness: to be bound to a partner of a different kind, the way two unlike animals do not belong under one yoke
Paul builds this word from two pieces: a prefix meaning "of a different kind" and the ordinary word for a yoke (ζυγός), the wooden beam that harnesses two animals so they pull one load together. The picture is of two creatures that were never meant to share a harness, straining against each other instead of with each other. The verb turns up once in the New Testament, and nowhere in surviving Greek writing before it, so Paul may well have coined it.
The image reaches back to Israel's laws about not mixing what was meant to stay separate: not breeding two kinds of animal, not sowing a field with two kinds of seed, not weaving two kinds of thread into one cloth. The Greek Old Testament uses the adjective behind this verb in exactly that setting, at Leviticus 19:19. A second law, the one forbidding an ox and a donkey to plow side by side in Deuteronomy 22:10, gives most readers the picture they carry, even though its Greek wording is different.
The prefix is doing real work. It does not mean simply "another"; it means "another of a different sort," the same shade Paul uses when he warns about "a different gospel" or about people who "teach a different doctrine" (ἑτεροδιδασκαλέω). The problem is not that the Corinthians have a partner but that they have the wrong kind of partner, joined to them for shared work and shared direction.
What the word means and what Paul is applying it to are two different questions. The picture of a mismatched yoking is stable and agreed. Who the mismatched partners are, and what activity is being forbidden, has been argued over for centuries.
What activity Paul forbids when he tells the Corinthians not to be mismatched with unbelievers.
- majorityParticipation in pagan cult, above all the meals eaten in idol temples; the paragraph's climax identifies the community as the temple of God, and the language ties closely to the idol-food discussion of 1 Corinthians 8 and 10.; William J. Webb, "What Is the Unequal Yoke (ἑτεροζυγοῦντες) in 2 Corinthians 6:14?" Bibliotheca Sacra 149/594 (1992): 163; Gordon D. Fee, "II Corinthians VI.14-VII.1 and Food Offered to Idols," New Testament Studies 23 (1977)
- minorityMarriage to an unbeliever, the reading long popular at a devotional level; critics answer that 1 Corinthians 7:12-16 tells believers already married to unbelievers to remain, which sits badly with a command to come out and be separate.; Jerome, Against Jovinian
- minorityThe ἄπιστοι in view are compromising or faithless members of the congregation rather than pagan outsiders.; Michael D. Goulder, in Novum Testamentum 36 (1994)
Disputed
Whether the ζυγ- root here pictures a yoke or the beam of a balance.
- majorityA yoke. The verb is formed on ζυγός, the yoke joining two draft animals, and its cognate adjective ἑτερόζυγος renders כִּלְאַיִם at Leviticus 19:19 LXX of breeding animals of diverse kind.; LSJ, s.v. ἑτερόζυγος; Murray J. Harris, The Second Epistle to the Corinthians, NIGTC (Grand Rapids: Eerdmans, 2005), 498-499
- minorityA balance. Since ζυγόν also denotes the beam of a scale (LSJ sense IV; cf. ἑτερόζυγος of a balance leaning to one side at Pseudo-Phocylides 15), the warning is against being unevenly weighted with unbelievers.; Joachim Camerarius, Commentary on the New Testament (Cambridge, 1642)