When Paul speaks about being unequally yoked with unbelievers (2 Cor. 6:14) we are reminded of Deut 22:10, which forbade the Israelites under Moses to plow with an ox and donkey yoked together. The ox was ritually clean, but the donkey was unclean (Deut. 14:3-8). Although in 1 Cor. 7:14 Paul teaches that the believing spouse sanctifies the other so that the children are clean, this being yoked with a spiritual donkey is not something to enter into intentionally.