Beware of false teaching…Jeremiah 23:30├ö├ç├┤32 (False Prophets)…30 "Therefore," says the Lord, "I am against these prophets who steal messages from each other and claim they are from me. 31 I am against these smooth-tongued prophets who say, 'This prophecy is from the Lord!' 32 I am against these false prophets. Their imaginary dreams are flagrant lies that lead my people into sin. I did not send or appoint them, and they have no message at all for my people. I, the Lord, have spoken!

Paul gives stern warning against false doctrines and false teachers

1 Timothy 1:3-11 "When I left for Macedonia, I urged you to stay there in Ephesus and stop those whose teaching is contrary to the truth. Don't let them waste their time in endless discussion of myths and spiritual pedigrees. These things only lead to meaningless speculations, which don't help people live a life of faith in God.

The purpose of my instruction is that all believers would be filled with love that comes from a pure heart, a clear conscience, and genuine faith.But some people have missed this whole point. They have turned away from these things and spend their time in meaningless discussions.They want to be known as teachers of the law of Moses, but they don't know what they are talking about, even though they speak so confidently.

He even lists various sinful characteristics and actions of these false teachers

1 Timothy 1:8-10 We know that the law is good when used correctly.For the law was not intended for people who do what is right. It is for people who are lawless and rebellious, who are ungodly and sinful, who consider nothing sacred and defile what is holy, who kill their father or mother or commit other murders.The law is for people who are sexually immoral, or who practice homosexuality, or are slave traders, liars, promise breakers, or who do anything else that contradicts the wholesome teaching that comes from the glorious Good News entrusted to me by our blessed God."

Covering basically the same ground as the Ten Commandments.

The things in this list, Paul claims, are “contrary to sound |literally healthy, wholesome| doctrine.” This doctrine, which is “according to the glorious gospel of the blessed God,” is held up as the standard by which we evaluate any teaching or attitude, not a man-made system of ethics or code of conduct.

This glorious gospel, the good news, proclaiming the entire person and work of the great Creator/Redeemer Jesus Christ, must be the basis for all “ wholesome ” teaching and lifestyle. Paul later wrote that these “wholesome words, even the words of our Lord Jesus Christ, and . . . the doctrine which is according to godliness

1 Timothy 6:3-5 Some people may contradict our teaching, but these are the wholesome teachings of the Lord Jesus Christ. These teachings promote a godly life."Anyone who teaches something different is arrogant and lacks understanding. Such a person has an unhealthy desire to quibble over the meaning of words. This stirs up arguments ending in jealousy, division, slander, and evil suspicions. These people always cause trouble. Their minds are corrupt, and they have turned their backs on the truth. To them, a show of godliness is just a way to become wealthy.