A false prophet can be recognized by the fact that he or she yields bad fruit — distrust, discord, confusion, wrangling, gossip, useless disputes, and divisions within the church, Jesus was very concerned about false prophets:
Mt 7:15 Jesus said to his disciples: “Beware of false prophets, who come to you in sheep’s clothing,but underneath are ravenous wolves.
Matthew 24: 4 Jesus answered: “Watch out that no one deceives you. 5 For many will come in my name, claiming, ‘I am the Christ, and will deceive many. 10 At that time many will turn away from the faith and will betray and hate each other, 11 and many false prophets will appear and deceive many people.
How do we tell who is a false prophet? Jesus tells us to look at the fruit:
Matthew 7: 16-20 By their fruits you will know them. Do people pick grapes from thorn bushes, or figs from thistles? Just so, every good tree bears good fruit, and a rotten tree bears bad fruit. A good tree cannot bear bad fruit, nor can a rotten tree bear good fruit. Every tree that does not bear good fruit will be cut down and thrown into the fire. So by their fruits you will know them.”
Writing for Sanity's Sake 