2 Corinthians 6:14 in the King James Version
Be ye not unequally yoked together with unbelievers: for what fellowship hath righteousness with unrighteousness? and what communion hath light with darkness?
Context
13 Now in return—I speak as to my children—you also open your hearts.
14 Don’t be unequally yoked with unbelievers, for what fellowship do righteousness and iniquity have? Or what fellowship does light have with darkness?
15 What agreement does Christ have with Belial? Or what portion does a believer have with an unbeliever?