Jude 1:11
9 But even when Michael the archangel was arguing with the devil and debating with him concerning Moses’ body, he did not dare to bring a slanderous judgment, but said, “May the Lord rebuke you!” 10 But these men do not understand the things they slander, and they are being destroyed by the very things that, like irrational animals, they instinctively comprehend. 11 Woe to them! For they have traveled down Cain’s path, and because of greed have abandoned themselves to Balaam’s error; hence, they will certainly perish in Korah’s rebellion. 12 These men are dangerous reefs at your love feasts, feasting without reverence, feeding only themselves. They are waterless clouds, carried along by the winds; autumn trees without fruit—twice dead, uprooted; 13 wild sea waves, spewing out the foam of their shame; wayward stars for whom the utter depths of eternal darkness have been reserved.
Pirkei Avot 5:19
Mishnah19 Whoever possesses these three things, he is of the disciples of Abraham, our father; and [whoever possesses] three other things, he is of the disciples of Balaam, the wicked. A good eye, a humble spirit and a moderate appetite he is of the disciples of Abraham, our father. An evil eye, a haughty spirit and a limitless appetite he is of the disciples of Balaam, the wicked. What is the difference between the disciples of Abraham, our father, and the disciples of Balaam, the wicked? The disciples of Abraham, our father, enjoy this world, and inherit the world to come, as it is said: “I will endow those who love me with substance, I will fill their treasuries” (Proverbs 8:21). But the disciples of Balaam, the wicked, inherit gehinnom, and descend into the nethermost pit, as it is said: “For you, O God, will bring them down to the nethermost pit those murderous and treacherous men; they shall not live out half their days; but I trust in You” (Psalms 55:24).
Notes and References
"... Jude’s reference to Balaam is dependent on the development of traditions about Balaam in postbiblical Judaism (on which see Vermes, “Balaam”; Ginzberg, Legends 3, 354–82), in which Balaam was almost always portrayed in a bad light, as “Balaam the villain,” one of the great enemies of the people of God. The disciples of Balaam are contrasted with the disciples of Abraham (Pirke Avot ̣ 5: the disciples of Balaam have “an evil eye, a greedy soul, and a haughty spirit,” and “go down to Gehenna”). Although according to the biblical account Balaam refused to be persuaded to curse Israel for the sake of monetary reward (Numbers 22:18; 24:13; but compare Deuteronomy 23:4; Nehemiah 13:2), Jewish traditional exegesis represented him as accepting Balak’s invitation out of greed for the large rewards promised him ..."
Bauckham, Richard Word Biblical Commentary: Jude-2 Peter (p. 81) Zondervan, 1983