The notion of a "soul mate" has its roots in the philosophy of Plato, not the Bible. Plato surmised that a prototypical human being was somehow split in two, resulting in our desperate search for the one person who can complete us.
The danger in this line of thinking (in addition to its idolatrous nature) resides in the question of how anyone can determine that someone is, in fact, his or her "soul mate." Most often, confirmation is based on emotional electricity, yet we all know how fickle emotions can be. Additionally, does it sound even remotely like God to let our future happiness depend on us finding "one person" out of millions of options? Can we possibly know enough in our twenties to figure this out?
In a biblical worldview, there is not "one right choice" for marriage, but rather, there are wise and foolish choices. We are encouraged to use wisdom, not destiny, as our guide. Paul's advice in 1 Corinthians 7 is pragmatic. There is no hint at all of finding "the one person" that God created "just for you." Do you think you'll sin sexually if you don't get married (1 Cor. 7:2)? Are you acting improperly toward a woman you could marry (1 Cor. 7:36)? If so, go ahead and get married. It's your choice, and God gives you that freedom.
Proverbs takes the same approach: "A wife of noble character who can find?" (Prov. 31:10). Proverbs addresses young, single men, telling them what to look for and what to avoid when choosing a wife, and the top thing to consider is this: "Charm is deceptive, and beauty is fleeting; but a woman who fears the Lord is to be praised" (Prov. 31:30). The Bible tells young men to search for a woman of character, not a pre-ordained "soul mate."
