The Bible warns in Matthew 24 against false prophets and false teachers. How do you recognize them?
In the Old Testament times if what a prophet prophesied came true He was real. So it was based on his telling the truth that he heard from God, In the new it is still based on truth. We are to test the prophets (spirits) by the Word of Truth. The main test is the truth about the son of God. False prophets always attack this central truth. We must test all things with the Word as the Bereans tested Paul. We need to know the Truth and the Truth shall set us free and the Truth is in Jesus. Yes I have seen many. All who teach salvation in any other way than the perfect and complete work of Christ.