Do not be yoked together with unbelievers. For what do righteousness and wickedness have in common? Or what fellowship can light have with darkness? 2 Corinthians 6:14
All followers of Jesus need to take the transforming message of the Gospel into their world. Sin separates us from God, and it is only through Jesus that we can have a relationship with the living God. As Jesus interacted with sinners, so must we. God has given us a network of friends and family. We need to tell the people in our lives about Jesus. But today's passage addresses more than sharing the Gospel. It warns Christians about entering into a partnership--a covenant--with nonbelievers. Let's focus on one important application of this passage.
Scripture warns a Christian not to marry a non-Christian. Yes, I know there are stories where the non-believing spouse comes to Christ after having married. Thank God for His grace. But we are not to presume on His grace. And there are plenty of sad stories where one spouse never came to Christ. This instruction is clear and straightforward: "Do not be yoked together with unbelievers." By the way, marriage starts with dating, so the same instruction applies to that phase of a relationship.
I know, I know, it's different with you. He's the nicest guy you've ever met. She is the girl of your dreams. Unfortunately, I see too many of these relationships five or ten years later. I see moms trying to raise children in the church with no support from their husbands. And I see husbands trying to lead their family in a godly way with opposition from their wives. There are always consequences to disobedience. Consequences will show up ... sooner or later.
Father, guard our hearts from the emotions of making bad relationship decisions that will haunt us for years to come. Remind us before we sin that there are consequences to sin. You designed and ordained marriage. Give us wisdom to follow Your instructions. In Jesus' name. Amen.