'But for corruption thou hast made Belial, an angel of hostility. All his dominions are in darkness, and his purpose is to bring about wickedness and guilt. All the spirits that are associated with him are but angels of destruction.'
Belial is also mentioned in the Fragments of a Zadokite Work (which is also known as The Damascus Document (CD)), which states that at the time of the Antichrist, "Belial shall be let loose against Israel, as God spake through Isaiah the prophet." (6:9). The Fragments also speak of "three nets of Belial" which are said to be fornication, wealth, and polution of the sanctuary. (6:10-11) In this work, Belial is sometimes presented as an agent of divine punishment and sometimes as a rebel, as Mastema is. It was Belial who inspired the Egyptian sorcerers, Jochaneh and his brother, to oppose Moses and Aaron. The Fragments also say that anyone who is ruled by the spirits of Belial and speaks of rebellion should be condemned as a necromancer and wizard.
Belial is also mentioned in the Testament of the Twelve Patriarchs. The author of the work seems to be a dualist because he presents Belial as God's opponent, not as a servant, but does not mention how or why this came to be. Simeon 5:3 says that fornication separates man from God and brings him near to Beliar. Levi tells his children to choose between the Law of God and the works of Beliar (Levi 19:1) It also states that when the soul is constantly disturbed, the Lord departs from it and Beliar rules over it. Naphtali (2:6, 3:1) contrasts the Law and will of God with the purposes of Beliar. Also, in 20:2, Joseph prophesies that when Israel leaves Egypt, they will be with God in light while Beliar will remain in darkness with the Egyptians. Finally, the Testament describes that when the Messiah comes, the angels will punish the spirits of deceit and Beliar (3:3) and that the Messiah will bind Beliar and give to his children the power to trample the evil spirits (18:12).
In The Martyrdom of Isaiah, Belial is the angel of lawlessness and is the ruler of this world.
"And Manasseh turned aside his heart to serve Beliar; for the angel of lawlessness, who is the ruler of this world, is Beliar, whose name is Matanbuchus." - Martyrdom of Isaiah 2:4
In Milton's Paradise Lost
Belial came last; than whom a Spirit more lewd
Fell not from Heaven, or more gross to love,
Vice for itself. To him no temple stood
Or altar smoked; yet who more oft than he
In temples and at altars, when the priest
Turns atheist, as did Eli’s sons, who filled
With lust and violence the house of God?
In courts and palaces he also reigns,
And in luxurious cities, where the noise
Of riot ascends above their loftiest towers,
And injury and outrage; and, when night
Darkens the streets, then wander forth the sons
Of Belial, flown with insolence and wine.
Witness the streets of Sodom, and that night
In Gibeah, when the hospitable door
Exposed a matron, to avoid worse rape.
-Paradise Lost, i. 490-504
Belial appears later in Mather's translation of the Goetia: the Lesser Key of Solomon as the 68th spirit.
Helpful tip: If you ever find yourself talking to a Belials, make sure to let him think he is better than you. Doing otherwise will prove unsuccessful.
You----- "Oh look! I found a dollar on the ground, sweet!"
Belials---"That's nothing one time I found 72 dollars on the ground..."
You-----" Awesome! I just got my black belt after all these years of hard work.
Belials--" I got 3 black belts in 2 months, I'm way better than you"
2nd dude: Yeah he does. you should see him play Diablo2, its insane!