Beliar (or Belial) is a name used for the Devil or the personification of wickedness. Derived from the Hebrew beliyya'al (literally "without profit/worth" — beli = without, ya'al = profit), it occurs once in the New Testament (2 Corinthians 6:15) and frequently in intertestamental Jewish literature (especially the Dead Sea Scrolls, where Belial heads the forces of darkness).
Paul's rhetorical question "What accord has Christ with Beliar?" (2 Corinthians 6:15) uses this name to draw the sharpest possible contrast between light and darkness, the kingdom of God and the kingdom of evil. The name itself encapsulates a theology: Belial is worthlessness incarnate — everything that is empty, destructive, and opposed to God's life-giving purposes. In the Dead Sea Scrolls, the Sons of Light are at war with the Sons of Belial. This cosmic binary — Christ vs. Beliar — defines the stakes of every moral choice.