Now, we are coming to the final stretch. One of the problems of Second Corinthians is that many people, including some Bible scholars, can not see the letter as a cohesive unit. Thus, they claim that Paul's command to separate from unbelievers is unconnected with the general context of the major themes of the letter, such as new leaders moving in after Paul and discrediting Paul's life and ministry, effectively poisoning Paul's relationship with the Corinthian church. But considering that Paul was one of the most brilliant men of his culture and furthermore that he was being carried along by the Holy Spirit, perhaps most of us have misunderstood the unity of this epistle. Perhaps we have fallen to the same error that Peter writes about in 2 Peter 3:6:
He writes the same way in all his letters, speaking in them of these matters. His letters contain some things that are hard to understand, which ignorant and unstable people distort, as they do the other Scriptures, to their own destruction.
Since our previous studies have shown that when Paul says the Corinthian believers must leave their yoke with non-Christians, that Paul is not referring to marriage, nor common associations. Rather, as we have already seen, Paul is telling them to judge those in the church who are false believers. So, which false believers are contaminating the church?
Paul makes this very clear in the latter part of his letter at 2 Co 11:2 I am jealous for you with a godly jealousy. I promised you to one husband, to Christ, so that I might present you as a pure virgin to him. 3 But I am afraid that just as Eve was deceived by the serpent’s cunning, your minds may somehow be led astray from your sincere and pure devotion to Christ. 4 For if someone comes to you and preaches a Jesus other than the Jesus we preached, or if you receive a different spirit from the Spirit you received, or a different gospel from the one you accepted, you put up with it easily enough.
5 I do not think I am in the least inferior to those “super-apostles.
...13 For such people are false apostles, deceitful workers, masquerading as apostles of Christ. 14 And no wonder, for Satan himself masquerades as an angel of light. 15 It is not surprising, then, if his servants also masquerade as servants of righteousness. Their end will be what their actions deserve.
This is the great and dangerous yokemate that is affecting the church - "super apostles". These men had seduced the Corinthians to follow a different Christ, a different spirit, and a different gospel! These "super apostles" were really false apostles and, in fact, unbelievers. These are the unbelievers that Paul commanded the believers to separate from. These false apostles are the ones the believers should not be yoked to.
This conclusion is actually quite safe and conservative. Paul's concern for false leaders and false messages in the church are seen throughout his letters. It is a common theme in the New Testament - as is the command to have nothing to do with these wolves in sheep's clothing. On the other hand, the idea that yoke = marriage is found nowhere in the Bible and the idea of Christians separating from non-Christians in general life is actually quite radical and contrary to the rest of Paul's writings.
It may help to replace the word, "false-apostle" for unbeliever to see if this opinion makes sense:
(obviously, I am changing a few highlighted words from the original)
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Do not be yoked together with false apostles. For what do righteousness and wickedness have in common? Or what fellowship can light have with darkness? What harmony is there between Christ and Belial? Or what does a believer have in common with an unbeliever? What agreement is there between the temple of God and idols? For we are the temple of the living God. As God has said:
“I will live with them
and walk among them,
and I will be their God,
and they will be my people.”
Therefore,
“Come out from them
and be separate,
says the Lord.
Touch no unclean thing,
and I will receive you.”
And,
“I will be a Father to you,
and you will be my sons and daughters,
says the Lord Almighty.”
Therefore, since we have these promises, dear friends, let us purify ourselves from everything that contaminates body and spirit, perfecting holiness out of reverence for God.
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I don't think any Christian should marry a non-Christian. But, if they do, the marriage is holy and they should stay together. However, under no circumstances should Christians endure a different Christ, spirit or gospel that the one presented in the Bible. Separate from this yoke as soon as possible.