The Lord's message to Jeremiah speaks directly to the church today that has been overtaken by false preachers. The text below (Jeremiah 23:9-40) speaks for itself I do not have to comment on it. Just take time and read it. Also read what Paul tells Timothy in 2 Timothy 3:1-9.
 
Judgment on False Prophets

9 My heart is broken because of the false prophets,

and my bones tremble.

I stagger like a drunkard,

like someone overcome by wine,

because of the holy words

the Lord has spoken against them.

10 For the land is full of adultery,

and it lies under a curse.

The land itself is in mourning—

its wilderness pastures are dried up.

For they all do evil

and abuse what power they have.

11 “Even the priests and prophets

are ungodly, wicked men.

I have seen their despicable acts

right here in my own Temple,”

says the Lord.

12 “Therefore, the paths they take

will become slippery.

They will be chased through the dark,

and there they will fall.

For I will bring disaster upon them

at the time fixed for their punishment.

I, the Lord, have spoken!

13 “I saw that the prophets of Samaria were terribly evil,

for they prophesied in the name of Baal

and led my people of Israel into sin.

14 But now I see that the prophets of Jerusalem are even worse!

They commit adultery and love dishonesty.

They encourage those who are doing evil

so that no one turns away from their sins.

These prophets are as wicked

as the people of Sodom and Gomorrah once were.”

15 Therefore, this is what the Lord of Heaven’s Armies says concerning the prophets:

“I will feed them with bitterness

and give them poison to drink.

For it is because of Jerusalem’s prophets

that wickedness has filled this land.”

16 This is what the Lord of Heaven’s Armies says to his people:

“Do not listen to these prophets when they prophesy to you,

filling you with futile hopes.

They are making up everything they say.

They do not speak for the Lord!

17 They keep saying to those who despise my word,

‘Don’t worry! The Lord says you will have peace!’

And to those who stubbornly follow their own desires,

they say, ‘No harm will come your way!’

18 “Have any of these prophets been in the Lord’s presence

to hear what he is really saying?

Has even one of them cared enough to listen?

19 Look! The Lord’s anger bursts out like a storm,

a whirlwind that swirls down on the heads of the wicked.

20 The anger of the Lord will not diminish

until it has finished all he has planned.

In the days to come

you will understand all this very clearly.

21 “I have not sent these prophets,

yet they run around claiming to speak for me.

I have given them no message,

yet they go on prophesying.

22 If they had stood before me and listened to me,

they would have spoken my words,

and they would have turned my people

from their evil ways and deeds.

23 Am I a God who is only close at hand?” says the Lord.

“No, I am far away at the same time.

24 Can anyone hide from me in a secret place?

Am I not everywhere in all the heavens and earth?”

says the Lord.

25 “I have heard these prophets say, ‘Listen to the dream I had from God last night.’ And then they proceed to tell lies in my name. 26 How long will this go on? If they are prophets, they are prophets of deceit, inventing everything they say. 27 By telling these false dreams, they are trying to get my people to forget me, just as their ancestors did by worshiping the idols of Baal.

28 “Let these false prophets tell their dreams,

but let my true messengers faithfully proclaim my every word.

There is a difference between straw and grain!

29 Does not my word burn like fire?”

says the Lord.

“Is it not like a mighty hammer

that smashes a rock to pieces?

30 “Therefore,” says the Lord, “I am against these prophets who steal messages from each other and claim they are from me. 31 I am against these smooth-tongued prophets who say, ‘This prophecy is from the Lord!’ 32 I am against these false prophets. Their imaginary dreams are flagrant lies that lead my people into sin. I did not send or appoint them, and they have no message at all for my people. I, the Lord have spoken!

False Prophecies and False Prophets

33 “Suppose one of the people or one of the prophets or priests asks you, ‘What prophecy has the Lord burdened you with now?’ You must reply, ‘You are the burden!* The Lord says he will abandon you!’

34 “If any prophet, priest, or anyone else says, ‘I have a prophecy from the Lord,’ I will punish that person along with his entire family. 35 You should keep asking each other, ‘What is the Lord’s answer?’ or ‘What is the Lord saying?’ 36 But stop using this phrase, ‘prophecy from the Lord.’ For people are using it to give authority to their own ideas, turning upside down the words of our God, the living God, the Lord of Heaven’s Armies.

37 “This is what you should say to the prophets: ‘What is the Lord’s answer?’ or ‘What is the Lord saying?’ 38 But suppose they respond, ‘This is a prophecy from the Lord!’ Then you should say, ‘This is what the Lord says: Because you have used this phrase, “prophecy from the Lord,” even though I warned you not to use it, 39 I will forget you completely.* I will expel you from my presence, along with this city that I gave to you and your ancestors. 40 And I will make you an object of ridicule, and your name will be infamous throughout the ages." 

 
The Problem of false prophets was not the problem of the OT alone, it is the problem for all ages. Paul as he passed on the mantel of leadership to Timothy warned him of false preachers. 
 

The Dangers of the Last Days

You should know this, Timothy, that in the last days there will be very difficult times. 2 For people will love only themselves and their money. They will be boastful and proud, scoffing at God, disobedient to their parents, and ungrateful. They will consider nothing sacred. 3 They will be unloving and unforgiving; they will slander others and have no self-control. They will be cruel and hate what is good. 4 They will betray their friends, be reckless, be puffed up with pride, and love pleasure rather than God. 5 They will act religious, but they will reject the power that could make them godly. Stay away from people like that!

6 They are the kind who work their way into people’s homes and win the confidence of* vulnerable women who are burdened with the guilt of sin and controlled by various desires. 7 (Such women are forever following new teachings, but they are never able to understand the truth.) 8 These teachers oppose the truth just as Jannes and Jambres opposed Moses. They have depraved minds and a counterfeit faith. 9 But they won’t get away with this for long. Someday everyone will recognize what fools they are, just as with Jannes and Jambres.

There is therefore the urgent need for true preachers of the word to sound forth the truth with urgency, for that is the only sure way to counter false preaching.