Dan knows this too well. Not only will his wife not share in eternal life, but their differences trickle down to practical matters as well. When facing a problem, they can’t rely on prayer together. When Dan is busy volunteering at his church, his wife is less than understanding. In addition, many arguments have started over the amount of Dan’s annual tithes. She just doesn’t understand the most important thing in his life.

“But he respects my faith.” A committed Baptist, my high school friend Jessica had heard the “Do not be yoked together with unbelievers” verse in 2 Corinthians dozens of times. But when she began dating Dominick, a non-Christian, she told friends it was OK because he believed in a higher power and was very interested in the supernatural. She argued that his interest and respect for people with devout beliefs was good enough to combat 2 Corinthians 6’s warnings that they’d have no common ground.

But slowly, Dominick’s intimate and intense influence on Jessica began to reshape her long-held convictions. He did believe in a god but had no commitment to him. So when I learned they were sleeping together, I was disappointed but not shocked. Paul wrote in 2 Corinthians 7:1 that we need to “purify ourselves from everything that contaminates body and spirit.” Letting someone who doesn’t hold our convictions and beliefs into the secret places of our heart surely can wear us down and contaminate the good there.

“But it’s my chance to witness.” My friend Lacey used to talk about her boyfriend Zach as if she had a secret time machine hidden somewhere. She would say, “Once he gets saved, he’ll be the perfect husband.” She acted as if it were a given.

I didn’t really know what to tell Lacey, because I could understand where she was coming from. I once met a non-Christian girl I really liked and quieted my inner warnings by saying, “It will be fine. She’ll become a Christian eventually.” But was my chief concern really the status of her salvation? No, selfish motivations were at play.

Several years ago, a woman named Zen Lee explained in the Columbia Standard why she dated only Christians. “I do not trust myself to desire the right things or to have the right motivations,” she wrote. “Maybe 99 percent of the time the motivations behind missionary dating are impure:  a need for attention or approval, [sexual desire], desire for companionship, longing to be understood, or a savior-complex. Every Christian should be wary of the secret motivations of the heart.”¹⁰

And even if our motivations were purely about a romantic interest’s salvation, missionary dating is a pretty ridiculous strategy. First off, we can’t save anyone – no matter how hard we work at it. It’s God’s call whose heart to work in, not ours. Second, the basic premise of missionary dating is purposeful deception. Do we really want to trick or lure somebody to Christ using our love as bait? I hope not.