What does unequally yoked mean in marriage?

When oxen are unequally yoked, they cannot perform the task set before them. Instead of working together, they are at odds with one another. So what does that have to do with biblically being unequally yoked?

What God says about being equally yoked?

Equally Yoked in Marriage Just like the oxen, he doesnt want you to be unequally yoked with a nonbeliever who will slow you down or who will deter you from your mission altogether. God wants you to have a missional marriage that serves him and his Kingdom; not an unequally yoked marriage.