Stand firm in your faith! Always be discerning by checking everything with the Word of God. "So then, brothers, stand firm and hold to the teachings we passed on to you, whether by word of mouth or by letter."  (2 Thes 2:15)

Stand up for the faith that was once for all entrusted to the saints! Don't ever let anyone cause you to stop doing that. "Dear friends, although I was very eager to write to you about the salvation we share, I felt I had to write and urge you to contend for the faith that was once for all entrusted to the saints. For certain men whose condemnation was written about long ago have secretly slipped in among you. They are godless men, who change the grace of our God into a license for immorality and deny Jesus Christ our only Sovereign and Lord." (Jude 1:3-4)

Be aware that many false teachers have gone out today. Test their teachings in the Word because they are deadly dangerous. "But there were also false prophets among the people, just as there will be false teachers among you. They will secretly introduce destructive heresies, even denying the sovereign Lord who bought them--bringing swift destruction on themselves." (2 Pe 2:1)

Finally, correct, rebuke and encourage because many are turning from true faith in Christ to heresy. Endure hardship from those who persecute you and tell you that you need to get involved in some "new" thing. Preach the gospel and live in obedience to the Word and Will of God. "Preach the Word; be prepared in season and out of season; correct, rebuke and encourage--with great patience and careful instruction. For the time will come when men will not put up with sound doctrine. Instead, to suit their own desires, they will gather around them a great number of teachers to say what their itching ears want to hear. They will turn their ears away from the truth and turn aside to myths. But you, keep your head in all situations, endure hardship, do the work of an evangelist, discharge all the duties of your ministry." (2 Tim 4:2-5)