Summary: Separation from the ungodly is a basic Bible doctrine. Verses 14 and 15 of this chapter are often applied to various sorts of alliances such as mixed marriages, improper business associations and religious fellowship. The idea of the unequal yoke comes f
THOUGHTS ABOUT THE PASSAGE:
It is often argued that we should stay in the midst of churches and bodies whose sins and follies we deplore, in the hope of saving them for God and mankind. Such reasoning has a good deal of force in the first stages of decline. A strong protest may arrest error and stop the gangrene. But as time advances, when the protests have been disregarded, and the arguments trampled underfoot; when the majority have clearly taken up their position against the truth—we have no alternative but to come out and be separate. The place from which we can exert the strongest influence for good is not from within, but from without. Lot lost all influence of his life in Sodom; but Abraham, from the heights of Mamre, was able to exert a mighty influence on its history. (F. B. Meyer).
Separation from the ungodly is a basic Bible doctrine. Verses 14 and 15 of this chapter are often applied to various sorts of alliances such as mixed marriages, improper business associations and religious fellowship. The idea of the unequal yoke comes from Deuteronomy 22:10 (quickview)  where it says "Thou shalt not plow with an ox and an ass together." To the Jew an ox was a clean animal and the ass wasn’t; and it was wrong to yoke them together (Deuteronomy 14:1 (quickview)  8). Paul is saying that in the same way, it is wrong for believers to be yoked together with unbelievers.
It is unfortunate that this important doctrine of separation has been so misunderstood and abused in recent years. On the one hand some sincerely zealous Christians have turned separation into isolation. They have restricted their association and fellowship to the point where they are fellowshiping in a phone booth and they cannot even get along with themselves. On the other hand, in reaction to this extreme position, other believers have torn down all the walls and will fellowship with anybody, regardless of what he believes or how he lives. We must remember that separation is not just a negative act but it is also a positive act of dedication to God. In our desire for doctrinal and personal purity, we must not isolate ourselves from those who desperately need our ministry and the Word of God.
In light of Paul’s counsel, what relationships with others, if any, do I need to change? I must be sure that I am always turning away from sin, not people, and turning to God in everything I do.