2 Corinthians 6:15 - Matthew Poole's English Annotations on the Holy Bible

And what concord hath Christ with Belial? By Belial, in this text, very good interpreters understand the devil; judging that the apostle here opposeth Christ, who is the Head of Believers and of the church, to him who is the head of all unbelievers, and the god of the world. The term is used only in this place in the New Testament, but very often in the Old Testament, to express men notoriously wicked and scandalous, Deuteronomy 13:13 Judges 19:22 1 Samuel 1:16, 1 Samuel 2:12 25:17 2 Samuel 16:7 2 Chronicles 13:7. The Hebrews themselves are not agreed in the etymology of it; Psalms 101:3, a wicked thing is called a thing of Belial (as may be seen in the margin of our bibles); so as the argument is drawn from our duty of conformity to our Head; Christ hath no fellowship with the devil, therefore we ought to have no unnecessary communion with such who manifest themselves to be of their father the devil, by their doing his works; nor hath Christ any communion with the sons of Belial. Or what part hath he that believeth with an infidel? What part or portion, that is, what society or communion, hath a believer with one that beheveth not? What hath he to do with him? It was a usual phrase amongst the Jews, Joshua 22:25,27. Some by this part understand, what portion in the life to come? In which sense it teacheth us, that we should maintain intimate and elective communion in this life only with such as we would gladly have our portion with in another life. But the most judicious interpreters think this is not intended in this place.