There was a young preacher who was trying to impress a congregation where he was candidating to become their pastor. As he opened his message he thought he would reference several of the parables to show that he had a good grasp of the scriptures. This is how he began...
“A man went down from Jerusalem to Jericho, and fell among thieves; and the thorns grew up and choked the man. After he recovered he met the Queen of Sheba, and she gave that man, a thousand talents of silver, and a hundred changes of raiment. And he got in his chariot and drove furiously, and as he was driving along under a big tree, his hair got caught in a limb and left him hanging here! And he hung there many days and many nights. The ravens brought him food to eat and water to drink. And one night while he was hanging there asleep, his wife Delilah came along and cut off his hair, and he fell on stony ground. And it began to rain, and rained forty days and forty nights. And he hid himself in a cave. Later he went on and met a man who said, ‘Come in and take supper with me.’ But he said, ‘I can't come in, for I have married a wife.’ And the man went out into the highways and hedges and compelled him to come in! He then came to Jerusalem, and saw Queen Jezebel sitting high and lifted up in a window of the wall. When she saw him she laughed, and he said, ‘Throw her down out of there,’ and they threw her down. And he said ‘Throw her down again,’ and they threw her down seventy-times-seven. And the fragments which they picked up filled twelve baskets full! Now, whose wife will she be in the day of the Judgment?'"
That introduction to the young preacher's sermon would be especially funny if it weren’t for the fact that too often God’s Word is horribly bungled by those who claim to be students of it. And many times it’s not a matter of misunderstanding or accidental misspeaking, which we are all prone to do at times. Rather, it’s a clear misrepresentation of the text because the person either failed to rightly divide the Word of Truth or has brought to it his own preconceived ideas. This kind of proclamation might sometimes be entertaining or even inspiring to the audience, but it is inexcusable before God and potentially identifies the speaker as a "false prophet."
Listen to the words of Jesus and consider how He says we are to determine the true prophet from the one who isn't.
“Beware of false prophets, who come to you in sheep’s clothing, but inwardly they are ravenous wolves. You will know them by their fruits. Do men gather grapes from thorn bushes or figs from thistles? Even so, every good tree bears good fruit, but a bad tree bears bad fruit. A good tree cannot bear bad fruit, nor can a bad tree bear good fruit. Every tree that does not bear good fruit is cut down and thrown into the fire. Therefore by their fruits you will know them.” (Matthew 7:15-20)
Notice carefully that it’s NOT the conduct or even the character of the one who is teaching that primarily reveals whether a preacher/teacher is of God or not. Jesus said it is by his “fruits” you will know him. Clearly, this isn’t a reference to the way he conducts his life, since outwardly he looks like one of the “sheep,” though inwardly he is a “ravenous” wolf. Then what is it by which we may determine if a person is worthy of being heard or whether we should turn a deaf ear? The answer is found in something else Jesus said in Matthew.
“Either make the tree good and its fruit good, or else make the tree bad and its fruit bad; for a tree is known by its fruit. Brood of vipers! How can you, being evil, speak good things? For out of the abundance of the heart the mouth speaks. A good man out of the good treasure of his heart brings forth good things, and an evil man out of the evil treasure brings forth evil things. But I say to you that for every idle word men may speak, they will give account of it in the day of judgment. For by your words you will be justified, and by your words you will be condemned.” (Matthew 12:33-35)
When we compare this with the aforementioned text we can see that Jesus is telling us that the "fruits" by which a person is identified as a true or false prophet are his "words" (i.e., the doctrine he teaches, cf. Isaiah 8:19-20). Through careful examination of his words (the content of his teaching) and comparing them to the Scripture, we learn the truth about his true identity. If his teaching matches the Scripture and represents it correctly, then we may safely conclude that the person is worthy to be heard. But if his words contradict the truth, intentionally misrepresent it, and/or simply bypass it altogether, then that person may well be classified a "false prophet." (cf. 1 John 4:1-3)
In fairness, there will always be some areas where good men disagree when it comes to biblical interpretation, but the core doctrines of the faith are absolutes that cannot be compromised. It is in these areas we especially need to evaluate the teaching of those we hear in order to discern if they are speaking the truth. Never be afraid to examine the words of the preacher/teacher in light of the Scriptures. If he is speaking the truth he will welcome the examination gladly. That’s what the Bereans were commended for doing (Acts 17:10-12) and what God desires from each of us. This means that all of us must have a working knowledge of the Scripture in order to discern the truth. You don’t have to be a Bible scholar, but you do have to be a man or woman of the Word.
I don’t believe that this exhortation from Scripture has ever been more necessary than it is today because there are so many opportunities for people to hear preaching/teaching from such a diverse number of speakers. Being mislead, even by someone that is genuinely sincere, can have eternal consequences for you and your family.