Prophecy is the ability to know what we could not know apart from divine revelation
The Bible is the only 'religious' book that speaks of future events with the same certainty that it speaks of past and present events. One of the primary reasons for predictive prophecy in the Old Testament was to establish God's credibility because only a Supreme Being can consistently and precisely predict the future in detail. In fact, He actually challenged the idol gods to
"Declare the things that are going to come afterward, that we may know that you are gods". And since this is impossible for them, He then goes on to say "Behold, you are of no account, And your work amounts to nothing; He who chooses you is an abomination." (Isaiah 41:3-4. Emphasis Added)
See God and His Bible
Some of the prophecies in the Bible are truly mind blowing.
For example, Daniel accurately described the succession of empires beginning with the Babylonians, winding down through the Medes and the Persians, the Greeks, and the Roman Empire which began to come into power around 241 B.C. Additionally Daniel 11 spans the centuries from Cyrus The Great to the reign of the antichrist and the end of the age. See The Rise And Fall Of The Empires
The many, many, Messianic prophecies in the Old Testament foretold virtually all facets of Jesus' life, including His birth, ministry, death, and His resurrection - hundreds of years in advance. This proved His legitimacy abd gave us a simple way to distinguish the true messenger from the false (and potentially dangerous) one. See Comparing Jesus With Other Religious Leaders... Why Jesus Is Without Equal
Contrary to popular belief, a prophet is not just someone who makes God inspired predictions about the future (foretelling). Those with God given authority to speak on His behalf (forth-telling) are also called prophets.
In other words, a prophet is a legitimate spokesperson for the Lord whether they are foretelling the future (predictive prophecy) or delivering a message that God wants delivered. Peter could not have been more clear when he said
"for no prophecy was ever made by an act of human will, but men moved by the Holy Spirit spoke from God". (2 Peter 1:21 NASB)
The False Prophets
Unfortunately, the Lord's legitimate prophets often found them selves in the murky world of false prophets who, interestingly, usually predicted good things - the victories, the blessings etc. to come. I do not believe they ever mentioned sin, repentance and any form of judgment.
For example, false prophets had told King Zedekiah that Nebuchadnezzar would not come against Judah. However Jeremiah's word to the king was that he would be "given into the hand of the king of Babylon!" (Jeremiah 37:17 NASB). Jeremiah further asked the king where the prophets were "who prophesied to you, saying, 'The king of Babylon will not come against you or against this land'? (Vs. 19)
If anything, the situation has gotten worse - at least in terms of numbers. In today's world false prophets abound - whether in churches around the country, on national television, or on one or another stage somewhere. People like Mike Bickle, Benny Hinn, Kim Clement, Kenneth Copeland, Pat Robertson etc. have all, at one time or another, made statements - some of which were pretty outrageous, others just plain daft. However, what they all had in common was that none of them came to pass.
For example, Benny HInn once said "The Lord also tells me to tell you in the mid 90's, about '94-'95, no later than that, God will destroy the homosexual community of America.... He will destroy it with fire. And many will turn and be saved, and many will rebel and be destroyed." (Benny Hinn. Orlando Christian Center, Dec. 31st, 1989)
There was (is?) even an organization titled the 'Apostolic Council of Prophetic Elders' - Bill and Jane Hamon, Dutch Sheets, Bill Lackie, and Cindy Jacobs were all members. All of these people are so deceived or have such large egos that they blurt our anything and everything that crosses their minds claiming 'revelation' from the Lord. Many of the prophecies are nothing but an endless torrent of mind numbing garbage.
The ones that comes to mind were made a few years ago
"Now, Lord, I ask you right now to put that catalytic germinating activating bringing forth anointing in everyone here and let it start working that everyone here before the year is out will be flowing like a river in the prophetic.” (National School Of The Prophets, Mobilizing The Prophetic Office Bill Hamon, 5/12/00, Session 11)
Or try this one from Lackie. It certainly sounds like he was smoking the same stuff Lewis Carroll did.
2006 is a year of advancement of the Kingdom of God through politics. He is spreading the Kingdom message throughout the World”. Lackie also said (talking about Jesus standing in the center of a very large stadium in heaven connected to a similar stadium on earth.
Jesus begins to call out the NEW NAME of the saint standing in the midst of the heavenly host. When he calls out the new name the person begins to vibrate from within and a heavenly light begins to permeate the cells of their body. As it expands from the inside out it explodes into a very bright light that extends approximately 50 feet radiating all around the person. This saint with a new name is transformed into a new warrior with great resolve. They understand their new name. They answer to their new name. They realize the new name represents who they have been all along but they are now this name all over through and through..."
And again, nothing has changed. They spew out this bilge day after day in an endless torrent of pretentious hot air that means absolutely nothing. This more recent one by Cindy Jacobs is about the 2017 being the supposed The Breakthrough Year . Apparently the number 17 in Scripture symbolizes "overcoming the enemy"and "complete victory." All Emphasis Mine
A New John 17 Movement
The Lord spoke to us that next year we would see a new John 17 movement begin where the prayer of Jesus will be answered. Many streams will run together until we see a river of revival flow across the earth. There will be major reconciliations between denominations, nations, and peoples.
This John 17 move will extend to families as well as there is a "focus on the family" where longstanding breaches between siblings, and between parents and their children are healed. God is calling for families to pray together and "light" the family altar. Strongholds in family systems are going to be broken in powerful and supernatural ways. This will even extend to strongholds of poverty, disease, alcoholism, and drug abuse.
The John 17 movements will align against injustice and religious strongholds as they decide together that they want a new move of the Holy Spirit.
We are hearing the words, New Wine, New Wine!...
The greatest harvest of souls the earth has known is upon us. Hundreds of thousands will be saved. The Middle East will experience a revival and this will extend into the evangelization of both the Arab and the Non-Arabic-speaking Muslims. Look to Egypt to be a leader in this revival and awakening.
The Glory of God is going to be poured out across the United States and these areas were specifically given as revival centers:
Los Angeles, California; Silicon Valley, Redding, California; Portland, Oregon; Seattle, Washington; Phoenix, Arizona; a new spring coming out of Colorado Springs, Colorado; Oklahoma; Austin, Texas; Kansas City, Missouri; Madison, Wisconsin; Indianapolis, Indiana; Nashville, Tennessee; Orlando, Florida; Fort Mills, South Carolina; Virginia; Annapolis, Maryland; Harrisburg, Pennsylvania; New York City; Boston, Massachusetts; as well as other cities and regions. 
Whoops sorry! Did I forget to mention that "Hanoi will become a beacon of light to the nations.
Okay! That is more then enough. There is only so much this garbage that I can read before the urge to throw up gets overwhelming. I don't remember who said this but it is beyond true - "their great swelling words should give one a sense of Déjà Moo... The distinct feeling one has heard all this bull before". I have absolutely no idea how some people sit there and soak them in month after month, year after year, without ever seeming to check whether any of them actually came true.
The Fate Of False Prophets
is not an enviable one
'Thus says the Lord God, "Woe to the foolish prophets who are following their own spirit and have seen nothing. "O Israel, your prophets have been like foxes among ruins. "You have not gone up into the breaches, nor did you build the wall around the house of Israel to stand in the battle on the day of the Lord. "They see falsehood and lying divination who are saying, 'The Lord declares,' when the Lord has not sent them; yet they hope for the fulfillment of their word. "Did you not see a false vision and speak a lying divination when you said, 'The Lord declares,' but it is not I who have spoken?"'" Therefore, thus says the Lord God, "Because you have spoken falsehood and seen a lie, therefore behold, I am against you," declares the Lord God. "So My hand will be against the prophets who see false visions and utter lying divinations. They will have no place in the council of My people, nor will they be written down in the register of the house of Israel, nor will they enter the land of Israel, that you may know that I am the Lord God. (Ezekiel 13:3-9 NASB)''
Jesus told us that some who are able to prophesy, cast out demons etc. will in the end hear Jesus say "I never knew you."
"Not everyone who says to Me, 'Lord, Lord,' will enter the kingdom of heaven, but he who does the will of My Father who is in heaven will enter. "Many will say to Me on that day, 'Lord, Lord, did we not prophesy in Your name, and in Your name cast out demons, and in Your name perform many miracles?' "And then I will declare to them, 'I never knew you; depart from me, you who practice lawlessness.' (Matthew 7:21-23)
Other verses warning about false prophets include
"Beware of the false prophets, who come to you in sheep's clothing, but inwardly are ravenous wolves. (Matthew 7:15 NASB)
"For false Christs and false prophets will arise and will show great signs and wonders, so as to mislead, if possible, even the elect. (Matthew 24:24 NASB)
But false prophets also arose among the people, just as there will also be false teachers among you, who will secretly introduce destructive heresies, even denying the Master who bought them, bringing swift destruction upon themselves. (2 Peter 2:1 NASB)
The Fate Of Those Who Listen To or Heed Them
Nor are the listeners are excused because false prophets told them lies. It is they who have given credibility to these fabrications.
The prophets prophesy falsely, and the priests rule on their own authority; and My people love it so! But what will you do at the end of it? (Jeremiah 5:31 NASB)
Then the Lord said to me, "The prophets are prophesying falsehood in My name. I have neither sent them nor commanded them nor spoken to them; they are prophesying to you a false vision, divination, futility and the deception of their own minds. "Therefore thus says the Lord concerning the prophets who are prophesying in My name, although it was not I who sent them--yet they keep saying, 'There will be no sword or famine in this land'--by sword and famine those prophets shall meet their end! "The people also to whom they are prophesying will be thrown out into the streets of Jerusalem because of the famine and the sword; and there will be no one to bury them--neither them, nor their wives, nor their sons, nor their daughters--for I will pour out their own wickedness on them. (Jeremiah 14:14-16 NASB)
In other words, we need to be extremely careful of those who claim the Lord told them this, that, or the other.
Testing The Prophets
As Paul said
do not despise prophetic utterances. But examine everything carefully; hold fast to that which is good; abstain from every form of evil. (1 Thessalonians 5:20-22 NASB)
John echoed his words,
Beloved, 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. (1 John 4:1 NASB) Note John's words equally apply to channeling.
Luckily, when it comes to predictive prophecy - foretelling a future event - it is not particularly difficult to distinguish between prophets who have been sent by the Lord and those who have not. The Old Testament emphasizes not one, but two tests of a true prophet.
1) This first one is usually misconstrued. It says
'But the prophet who speaks a word presumptuously in My name which I have not commanded him to speak, or which he speaks in the name of other gods, that prophet shall die.' "You may say in your heart, 'How will we know the word which the Lord has not spoken?' "When a prophet speaks in the name of the Lord , if the thing does not come about or come true, that is the thing which the Lord has not spoken. The prophet has spoken it presumptuously; you shall not be afraid of him. (Deuteronomy 18:20-22 NASB)
However, one needs to read the words very carefully since, contrary to popular opinion, they do not teach us that any prophet whose words come true is a true prophet. The text only says that any prophet whose words do not come true is a false prophet.
2) Read what was said five chapter earlier.
"If a prophet or a dreamer of dreams arises among you and gives you a sign or a wonder, and the sign or the wonder comes true, concerning which he spoke to you, saying, 'Let us go after other gods (whom you have not known) and let us serve them,' you shall not listen to the words of that prophet or that dreamer of dreams; for the Lord your God is testing you to find out if you love the Lord your God with all your heart and with all your soul. (Deuteronomy 13:1-3 NASB)
These verses give us the acid test of a true prophet... his adherence to the Word of God.
Regardless of whatever sign or wonder we are presented with, if it at all contradicts God's word the prophet or "dreamer of dreams" was to be put to death, "because he has counseled rebellion against the Lord your God who brought you from the land of Egypt and redeemed you from the house of slavery, to seduce you from the way in which the Lord your God commanded you to walk. So you shall purge the evil from among you. (Deuteronomy 13:5 NASB)
For example, it is not exactly unknown for a man to tell a woman that God told him he was to marry her. However, this cannot possibly be from God if one of them was already married.
Was Jonah A False Prophet?
While we cannot be exactly sure how the Word of the Lord 'came' to Jonah, we know that he was told to "cry against Nineveh" because of their wickedness (Jonah 1:2). See How The Bible Was Written
Jonah was very likely familiar with Jeremiah 18 from which Jonah knew that if the Ninevites were to repent they would be spared.
"At one moment I might speak concerning a nation or concerning a kingdom to uproot, to pull down, or to destroy it; if that nation against which I have spoken turns from its evil, I will relent concerning the calamity I planned to bring on it. "Or at another moment I might speak concerning a nation or concerning a kingdom to build up or to plant it; if it does evil in My sight by not obeying My voice, then I will think better of the good with which I had promised to bless it. (Jeremiah 18:7-10 NASB)
This didn't sit well with the prophet and probably accounts for the fact that the he took off in the opposite direction when first told to go to Nineveh and warn them of God's impeding judgment. In all fairness it is hard to condemn Jonah for his actions. The Assyrians, who had carted the northern kingdom of Israel into exile, were one of the most cruel kingdoms in ancient days with a terrible reputation for sparing no one. Jonah's feelings would have been akin to telling a Jew to go Nazi Germany and tell the Gestapo to repent.
After the incident with the whale, Jonah was again instructed to "Arise, go to Nineveh the great city and proclaim to it the proclamation which I am going to tell you." Following which, Jonah who had probably developed a distinct aversion to fish,
... arose and went to Nineveh according to the word of the Lord. Now Nineveh was an exceedingly great city, a three days' walk. Then Jonah began to go through the city one day's walk; and he cried out and said, "Yet forty days and Nineveh will be overthrown." (Jonah 3:2-4 NASB)
But the fact that city was not overthrown in 40 days is often used by today's false prophets to explain why their 'prophecies' also fail to come to pass.
This is so much a matter of common sense that I am not sure why I am writing about it at all.
Jonah's prophecy was a conditional one that, thankfully, applies to us as much as it applied to the Assyrians. Verse 5 says "Then the people of Nineveh believed in God; and they called a fast and put on sackcloth from the greatest to the least of them"
When God saw their deeds, that they turned from their wicked way, then God relented concerning the calamity which He had declared He would bring upon them. And He did not do it. (Jonah 3:9-10 NASB)
However conditional prophecies only apply to sin and judgment etc. Inasmuch as if the person repents, the Lord stays His hand. If they do not, He does what He said He would do. In this case the Assyrian's repentance didn't last and they soon relapsed into their old ways. It fell to the prophet Nahumto proclaim to the Ninevites that Divine trouble was brewing and it was only a matter of time before it came to the boil. They were once again the target of God's wrath -
Jonah's mission was a call to repentance, that typified God's message to the world. Nahum's mission was to pronounce on Nineveh its doom... a forerunner of the judgment to come.
Many people use 1 Corinthians 13:9 (For we know in part and we prophesy in part (Gk. meros) as an excuse for the scores of false prophecies floating around today. They explain that "prophesy in part" means that the prophet may mix error with truth.
Translated from the Greek word meros the English 'part' means a portion or segment of a whole. See for example
They gave Him a piece (Gk. meros) of a broiled fish; (Luke 24:42 NASB)
Then the soldiers, when they had crucified Jesus, took His outer garments and made four parts (Gk. meros), a part (Gk. meros) to every soldier and also the tunic; now the tunic was seamless, woven in one piece. (John 19:23 NASB)
and kept back some of the price for himself, with his wife's full knowledge, and bringing a portion (Gk. meros) of it, he laid it at the apostles' feet. (Acts 5:2 NASB)
Although crucial, all of God's prophesies are usually only a piece of the complete picture. However, as shown above, they were never wrong or 'mistaken'.
If we hold that even legitimate prophets can make 'mistakes', then how in the world do we determine who is a false prophet? How do we know whom we can trust without reservation?
One of the problems in the church to day is the never ending stream of people who seem to sincerely believe that they have heard from the Lord and are not usually shy about sharing the messages with others - often introduced with a "Thus saith the Lord".
The problem being that unless the person is actually quoting or paraphrasing Scripture, the statements tend to be so general that t is close to impossible for their listeners to sort out what may be from the Lord and what might be the effect of too much pepperoni pizza the night before.
For example, if a person were to get up in the church congregation and say something like, "God says He will be glorified in our midst and bring people to Himself through this church."
No doubt He will, but it will be impossible to conclude that this word has or has not been fulfilled. Even if we see no new converts, we can suppose that some have come to Christ in the workplace and through the giving and example of our church members. 
I do not know exactly how we are supposed to tell truth from error in cases like this. All I can say is if something pops into your head, it makes sense not to immediately jump up and repeat it. This because not everything that crosses our minds is from the Father and we should not be egotistical enough to think so.
Give yourself a few minutes to 'settle down' because it is often the case that a little reflection lends a little wisdom to what one says and how one says it. Or even if one should say anything at all.
If the words really were from the Father, one can be pretty certain that they will not lose their impact if delayed for a few minutes.
The fact is that prophets, both true and false, have always been with us. However, what is interesting is false prophets usually spoke of the good things - the victories, the blessings etc. to come. I do not believe they ever mentioned sin, repentance and any form of judgment.
As mentioned the false prophets had told King Zedekiah that Nebuchadnezzar would not come against Judah. And as Cindy Jacobs prophecy for 2017 shows, nothing has changed.
 Cindy Jacobs. Word of the Lord for 2017 (posted December 29th, 2016)
 [Randy Alcorn. Is the Gift of Prophecy in the Church Today Handled Carefully and with Discernment? Eternal Perspective Ministries. https://www.epm.org/resources/2010/Mar/29/gift-prophecy-church-today-handled-carefully-and-d/