false teachers

False teachings according to the Zondervan Bible Dictionary:

Scripture repeatedly warns against false teachings, which deny or distort some aspect of the gospel. The origin of such teachings is attributed either to human error or to demonic inspiration.

Examples of false teachings
Rev 2:14-15 See also Mt 5:19; 2Th 2:1-2; 1Ti 4:1-3; Rev 2:20

Qualities of false teachings
They are valueless Mt 15:9 pp Mk 7:7 See also Isa 29:13; Eph 5:6; Col 2:20-23; 1Ti 1:3-7
They are destructive in their nature 2Pe 2:1 See also Mt 7:15; Ac 20:29-30; Tit 1:10-11
They have the capacity to lead people astray Ac 20:30 See also Eph 4:14; 1Ti 6:20-21; Heb 13:9; 2Pe 2:14-15; 1Jn 2:26
They may be popular 2Pe 2:2 See also Mt 24:4-5 pp Mk 13:5-6; 2Ti 4:3; 2Pe 2:18-19; 1Jn 4:1-5
They may be accompanied by miraculous signs Mt 24:24 pp Mk 13:22 See also 2Th 2:9-10; Rev 13:11-15

The origin of false teachings
Demonic inspiration 1Ti 4:1-2 See also 2Co 11:3-4; 1Jn 4:1-3; Rev 16:13-14
Human error 2Pe 2:3 See also Col 2:8; 1Ti 6:20-21

Discerning false teachings
By their content 1Jn 4:2-3 See also 1Co 12:3; 1Jn 2:20-23; 2Jn 7-11
By the teacher’s lifestyle Mt 7:15-20 See also 2Co 11:20; 1Jn 3:7-10; Jude 4
By their effects 1Ti 6:3-5 See also 1Ti 1:3-4; 2Ti 2:16-18; Rev 2:20

The antidote to false teachings
Holding fast to the true gospel 1Jn 2:24 See also Gal 1:6-9; 1Ti 1:18-20; 2Ti 1:13-14
Shunning false teachers Ro 16:17-18 See also 2Ti 3:1-9; Tit 3:9-11; 2Jn 9-11