In the new testament, we are warned about false human teachers, but there are also deceiving spirits to avoid. Jesus warns us about false prophets and false messiahs in Matt 24:24 and Mark 13:22. Colossians 2:8-10 says to reject corrupt theology based on the philosophies of worldly spiritual teachings. 1 John 4:1-4 says to test the spirits and ignore the ones that steer people away from what Jesus and his apostles taught. Gal 1:8 warns about false gospel preached by anyone including fallen angels. 2 Cor 11:13-15 says that false teachers pretending to be godly is like how Satan pretends to be an angel of light. Also, Col 2:18 says angels shouldn’t be worshiped or prayed to.