We read in the NT much about false teachers…see listing below, but here is an example from the OT.
Mic 2:11 If a man walking in the spirit and falsehood do lie, saying, I will prophesy unto thee of wine and of strong drink; he shall even be the prophet of this people.
Micah 2:11 John Gill
If a man walking in the spirit and falsehood do lie,…. Who pretends to be a prophet, and a spiritual man, and to be under the inspiration and influence of the Spirit of God, but utters nothing but lies and falsehoods; or who is actuated by a spirit of falsehood and lying;
or, as in the margin, “walks with the wind, and lies falsely” (u); is full of wind and vanity; “after the wind” (w); and follows the dictates of his vain mind, and coins lies, and speaks false things:
saying, I will prophesy unto thee of wine and of strong drink; or “drop a word unto thee” (x); that there will be good times, and nothing but good eating and drinking; and that men need not fear such dismal things befalling them as the prophets of the Lord spoke of; but may be cheerful and merry, and drink wine and strong drink, and not be afraid of their evil tidings: or, for wine and strong drink (y), so Kimchi;
and the meaning is, that if they would give him a cup of wine, or a draught of strong drink, he would prophesy good things to them; the reverse of what is before said, as that they should continue in their land, and not depart from it; that this should be their rest, and they should remain therein, and not be destroyed in it, or cast out of it:
he shall even be the prophet of this people; a “dropper” (z) to them; see Mic 2:6; such an one shall be acceptable to them; they will caress him, and prefer him to the true prophets of the Lord; which is mentioned to show the temper of the people, and how easily they were imposed upon, and their disrespect to the prophets of the Lord, as in Mic 2:6; to which subject the prophet here returns, as Kimchi observes.
(u) הולך רוח ושקר כזב “qui ambulat cum vento et falsitate mentiatur”, Piscator; “ambulantem cum vento et fasitate mendacem”, Cocceius. 
So Hillerus in Burkius. (x) אטיף לך “stillabo tibi”, Pagninus, Montanus, Junius & Tremellius, Piscator, Burkius. (y) ליין “pro vino”, Pagninus, Montanus, Junius & Tremellius, Piscator, Drusius. (z) מטיף “stillator”, Junius & Tremellius, Piscator, Drusius, Cocceius.
Act 13:6 And when they had gone through the isle unto Paphos, they found a certain sorcerer, a false prophet, a Jew, whose name was Barjesus:
Rom 13:9 For this, Thou shalt not commit adultery, Thou shalt not kill, Thou shalt not steal, Thou shalt not bear false witness, Thou shalt not covet; and if there be any other commandment, it is briefly comprehended in this saying, namely, Thou shalt love thy neighbour as thyself.
1Co 15:15 Yea, and we are found false witnesses of God; because we have testified of God that he raised up Christ: whom he raised not up, if so be that the dead rise not.
2Co 11:13 For such are false apostles, deceitful workers, transforming themselves into the apostles of Christ.
2Co 11:26 In journeyings often, in perils of waters, in perils of robbers, in perils by mine own countrymen, in perils by the heathen, in perils in the city, in perils in the wilderness, in perils in the sea, in perils among falsebrethren;
Gal 2:4 And that because of false brethren unawares brought in, who came in privily to spy out our liberty which we have in Christ Jesus, that they might bring us into bondage:
2Ti 3:3 Without natural affection, trucebreakers, falseaccusers, incontinent, fierce, despisers of those that are good,
Tit 2:3 The aged women likewise, that they be in behaviour as becometh holiness, not false accusers, not given to much wine, teachers of good things;
2Pe 2:1 But there were false prophets also among the people, even as there shall be false teachers among you, who privily shall bring in damnable heresies, even denying the Lord that bought them, and bring upon themselves swift destruction.
1Jn 4:1 Beloved, believe not every spirit, but try the spirits whether they are of God: because many false prophets are gone out into the world.
Rev 16:13 And I saw three unclean spirits like frogs comeout of the mouth of the dragon, and out of the mouth of the beast, and out of the mouth of the false prophet.
Rev 19:20 And the beast was taken, and with him the falseprophet that wrought miracles before him, with which he deceived them that had received the mark of the beast, and them that worshipped his image. These both were cast alive into a lake of fire burning with brimstone.
Rev 20:10 And the devil that deceived them was cast into the lake of fire and brimstone, where the beast and the false prophet are, and shall be tormented day and night for ever and ever.
Rainbow Trout 