And after six days Jesus took with him Peter and James, and John his brother, and led them up a high mountain by themselves. And he was transfigured before them, and his face shone like the sun, and his clothes became white as light. And behold, there appeared to them Moses and Elijah, talking with him. And Peter said to Jesus, “Lord, it is good that we are here. If you wish, I will make three tents here, one for you and one for Moses and one for Elijah.” He was still speaking when, behold, a bright cloud overshadowed them, and a voice from the cloud said, “This is my beloved Son, with whom I am well pleased; listen to him.” When the disciples heard this, they fell on their faces and were terrified. But Jesus came and touched them, saying, “Rise, and have no fear.” And when they lifted up their eyes, they saw no one but Jesus only. Matthew 17:1–8, ESV
From what I have observed, and please correct me if I am wrong, it seems that telling a false prophet or false teacher from those who are true is not as difficult as some think. Those who are true understand and teach the centrality of our Lord Jesus Christ in all things. It really is all about Him and His glory. On the other hand, those who are false will focus nearly all of what they preach and teach from the perspective of Man. Instead of teaching our role in the Kingdom as subjects of God, they expound things for the benefit of what is fair or what seems right to men, making excuses for fleshly indulgences and not calling it sin. They refuse to accept that the Bible teaches that sin is what separates Men from God and those who die in their sin will spend eternity in Hell. Of course these teachings echo the lie that our enemy told Eve in the Garden, “Has God really said?”