For a Christian to marry a non-Christian is not really an option if the Christian is to remain obedient to the Lord. For a Christian to date a non-Christian is less problematic, but still unwise, given that the ultimate intent of dating is to find a marriage partner.
A Christian considering marriage has some clear guidance in 2 Corinthians 6:14, which says, “Do not be yoked together with unbelievers.” The imagery comes straight from the farm: if two incompatible animals are sharing the same yoke, they will be constantly working against each other. It’s much better to yoke similar animals. The illustration has a spiritual application: two people united in some way and working closely together should be of like nature and share similar spiritual goals. It won’t do to tie oneself to an unbeliever and expect good results.
To be fair to the text, 2 Corinthians 6 does not specifically mention marriage, but it certainly has implications for marriage. What closer yoke can there be than the marriage bond? For a Christian to knowingly enter a marriage union with an unbeliever is to be “unequally yoked,” to use the ESV’s wording. Instead of a match made in heaven, it will be a mismatch made on earth. The same passage pointedly asks, “What does a believer have in common with an unbeliever?” (2 Corinthians 6:15).
So, what about a Christian dating a non-Christian? They aren’t being “yoked together,” so the command of 2 Corinthians 6:14 would not seem to apply. However, there are other considerations:
First, for a Christian to date a non-Christian is inadvisable because of the purpose of dating. If, as mentioned, dating is the precursor of marriage, then dating a non-Christian would be a dead-end relationship, romantically. With no biblical marriage possible, a Christian would have no reason to date a non-Christian. If you don’t want to catch a fish, don’t throw your line in the water.
Second, matters of the heart have a way of blinding us to other priorities. We see this in the lives of Samson, who, for all his strength, kept falling in love with the wrong women (Judges 14:1–3; 16:4); and King Solomon, who, for all his wisdom, allowed himself to be swayed into sinful behavior (1 Kings 11:4). Romantic attachment is a powerful force, and it can overwhelm sound judgment and godly commitment.
Third, the Bible says, “Do not be misled: ‘Bad company corrupts good character’” (1 Corinthians 15:33). Of course, not all non-Christians can be called “bad company” in that not all exert an overtly negative influence. But there’s an underlying spiritual principle always at work: light and darkness do not mix (2 Corinthians 6:14). The unbeliever is “darkness,” and the believer is “light in the Lord.” We are called to “live as children of light” (Ephesians 5:8). At the very least, the believer and unbeliever will probably have different views of what dating should be. Having any kind of close, romantic relationship with an unbeliever invites trouble and carries the risk of turning into something that hinders one’s walk with Christ.
Some Christians engage in “missionary dating,” which is a Christian dating a non-Christian with the goal of leading that person to faith in Christ. Evangelizing someone is a noble goal, and there are doubtless cases in which individuals have been saved through missionary dating, but it’s not really the goal of a dating relationship. For the three reasons discussed above, missionary dating is not a good idea.
Deciding whether to date a non-Christian is not just a relational choice; there are spiritual choices to be made, as well, regarding an uncompromised faith. We can and should build quality friendships with unbelievers, but that is as far as it should go. We are in spiritual union with other believers in the Body of Christ (Romans 12:5), and our most important relationships should be with fellow believers.