"Be Not Unequally Yoked"
Paul admonished the Corinthian Christians, “Be not unequally yoked together with unbelievers; for what fellowship hath righteousness with unrighteousness? And what communion hath light with darkness?” (2 Corinthians 6:14). This statement often has been applied to the question of marriage, with the subsequent conclusion that Christians are commanded not to marry non-Christians. However, this interpretation creates several problems.
First, marriage is not under discussion in the context. Great care must be taken to avoid misapplying the principles taught in a given passage. The application of a passage must be accurate. For example, to apply the injunction “taste not” (Colossians 2:21) to eating chocolate would be a misapplication on two counts. First, it assumes that chocolate is included in the category of substances being forbidden in the context. Second, it fails to perceive the fact that “taste not” was what the opponents of Paul were enjoining. They were wrong in their making of a law that God had not made. Likewise, the prohibition of not being unequally yoked would have to be demonstrated to apply to marriage.
Second, if forming a marriage between a Christian and non-Christian is being forbidden, the only way to repent of such an action would be to sever the marriage. The only way to repent of an illicit relationship is to terminate the relationship (cf. Ezra 10:11; Mark 6:18; 1 Corinthians 6:9-11). Those who fail to separate would be subject to church discipline (1 Corinthians 5:1ff.). Paul explicitly stated in the context to “come out from among them, and be ye separate” (2 Corinthians 6:17). But this inevitable conclusion would contradict Matthew 19:9, where Jesus stated that there is one and only one grounds for divorce, i.e., fornication—not marriage to a non-Christian.
Third, if marriage to a non-Christian is forbidden, then non-Christians sin when they marry each other. The non-Christian who marries another non-Christian is guilty of not marrying a Christian.
Fourth, if the Christian sins when he marries a non-Christian, what about that non-Christian whom the Christian marries? That non-Christian would not be sinning since he/she is marrying a Christian. Hence, the very action that is sin for one (the Christian) is righteous and proper for the other (non-Christian)!
Fifth, such an interpretation of 2 Corinthians 6:14 implies that marriage is a “Christian” institution. Yet the marriage relationship was formed by God at Creation thousands of years before Christianity was introduced onto the planet (Genesis 2:24). God’s marriage laws apply equally to all people in all periods of Bible history. No one prior to the cross of Christ married a Christian! Yet marriages contracted prior to Christianity were valid if contracted in harmony with God’s marriage laws (i.e., in accordance with Genesis 1:27, 2:24, Matthew 19:3-12, Romans 7:1-3, and 1 Corinthians 7:1-40).
All persons who choose to be married are required by God to “marry in the Lord” (1 Corinthians 7:39). That is, one must marry in harmony with God’s laws, even as children are to obey their parents “in the Lord” (Ephesians 6:1), i.e., compliant with parental instructions that are in harmony the will of Christ. Marriage of a Christian to a non-Christian may well be fraught with peril. It may be at times inexpedient, unwise, or extremely dangerous spiritually. However, the Bible does not teach that it is sinful.
So what does this passage mean? It means that Christians should not contract any social arrangement (e.g., business) with another that would require the Christian to violate God's law. For example, suppose you form a business partnership with a non-Christian by opening a restaurant. Afterwards, you learn that your partner intends to serve alcohol and sell cigarettes to customers. Or perhaps you find that he is cheating customers by overcharging them. Or you discover that he is not reporting profits to the IRS. In each of these cases, you as a Christian would find yourself in an "unequal yoke," i.e., a relationship that would necessarily involve you in wrong doing. What should the Christian do in such a case? "Come out from among them," i.e., sever the business partnership.