Does unequally yoked only apply to marriage?

Les explains that most people, when they look at this verse, think only of an unequal marriage, but he stresses that it does not have to stop with marriage. It can enter into anything where people have to work together for a common cause. As soon as an unbeliever and a believer are put together, they are just as unequally yoked as an ox with a donkey, or as making a garment with linen and wool. He also notes that many marital problems people call about are cases of being unequally yoked one way or another, and those problems began before they ever got married. He illustrates this with a young lady who was crying because her husband had become a wife beater; he asked whether she knew he had that potential when they were going together, she said maybe a little, and he asked why she married him anyway. She said he was the star football player, which Les calls a mighty poor criterion for husband material, though he notes a football player can be a good husband. He concludes that choosing a husband just because he is a star football player is an unequal yoke, and that people do not change; many walk into problems with their eyes wide open, thinking they can change the person somewhere down the road.