This verse is used to warn (and sometimes clobber) people who are falling in love with a non-Christian or teenagers hanging out with non-Christian friends.It is often quoted to encourage Christians to not enter into business with someone who is not a Christian. I even heard of a case in which a business owner was coerced into selling his multi-million dollar business to his non-Christian business partner for chump change through his pastor's misuse of this verse.

Other versions of the Bible say unequally yoked instead of mismated. The original is a powerful image. A yoke is a wooden bar or frame used to join draft animals at the heads or necks so that they pull together. When animals are yoked correctly, the result is increased productivity and less strain. But when they are unequally yoked, the result can be burnout, chaos, or worse.

This is written for those who truly believe, and its application is for every situation in life. We need to make sure that we are not joining unbelivers in pursuit of the things that dishonor God. The believing employee working for a dishonest boss or company is unequally yoked. The believing friend who is slowly becoming more and more insensitive to sin by hanging out with his unbelieving friends is unequally yoked. The believing family who is going broke trying to keep up materially with the neighbors is unequally yoked. Christians who are so in love with the world that they can't see how it's choking the life of God out of them are unequally yoked. Darknes and light cannot have fellowship.

If you and I are the temple of the Holy Spirit and we are pursuing the things of this world, we have set up idols in the God's house. We have become yoked to the system of this world rather than to Christ. His yoke is easy, his burden is light, but the world's yoke drags us around like a Yorkshire terrier tied to a bull.

But not every relationship with unbelievers ends up like this. Sometimes people who don't share the faith will have common goals. You may even find that some "unbelievers" or "non-Christians" believe and respect the rules more than some "Christians." Sometimes Christians partnering with non-Christians leads to God's glory. And sometime believers that marry unbelievers find God leading the spouse to faith in Christ. This verse is talking about truly uneven spiritual and moral pairings, and each believer, in step with the Spirit of God, must evaluate his own situation and come to his or her own conclusion

Using a verse to control or manipulate rather than inform and guide is misguided at best. Nobody listens to this advice unless the Spirit of God is at work in their hearts. And here's why: This verse is written for those who BELIEVE. Believers believe. It's what they do. When the Holy Spirit works in a person's heart, they hear God's word and respond to it. But the person who has hardened his heart will not hear even if an angel brings the message.