Dear friends, do not believe every spirit, but test the spirits to see whether they are from God, because many false prophets have gone out into the world.
I John 4:1
It is sad to think that there are people in the world trying to pass themselves off as men or women of God. Any time we hear someone preaching it is up to us to make sure they are speaking the truth. Listen closely, are they pointing us to Christ? Do they mention Christ? Take notes, go back and read the scripture to make sure what was said was right. If this were not important we wouldn't have a warning about it in the Bible. Ask God to help you know the truth - He will help you.