Jude 1:16

16 grumblers, malcontents. Like Israel in the wilderness (v. 5; 1 Cor. 10:10), the false teachers resist God’s will, perhaps by complaining about the law’s restrictions on their behavior.

loud-mouthed boasters. These may have been claims to having visionary experiences (v. 8), freedom from the law (vv. 4, 8), or possession of the Holy Spirit (vv. 18, 19).

showing favoritism to gain advantage. They show partiality to the rich members of the church (James 2:1–4), and perhaps go on to adapt their teaching to please the influential in their audience.