John 10:5

They are of the world: therefore speak they of the world, and the world heareth them. We are of God: he that knoweth God heareth us; he that is not of God heareth not us. Hereby know we the spirit of truth, and the spirit of error.

As ye have therefore received Christ Jesus the Lord, so walk ye in him: Rooted and built up in him, and stablished in the faith, as ye have been taught, abounding therein with thanksgiving. Beware lest any man spoil you through philosophy and vain deceit, after the tradition of men, after the rudiments of the world, and not after Christ. For in him dwelleth all the fulness of the Godhead bodily. And ye are complete in him, which is the head of all principality and power:

And he gave some, apostles; and some, prophets; and some, evangelists; and some, pastors and teachers; For the perfecting of the saints, for the work of the ministry, for the edifying of the body of Christ: Till we all come in the unity of the faith, and of the knowledge of the Son of God, unto a perfect man, unto the measure of the stature of the fulness of Christ: That we henceforth be no more children, tossed to and fro, and carried about with every wind of doctrine, by the sleight of men, and cunning craftiness, whereby they lie in wait to deceive; But speaking the truth in love, may grow up into him in all things, which is the head, even Christ:

And he said unto them, Take heed what ye hear: with what measure ye mete, it shall be measured to you: and unto you that hear shall more be given.

Cease, my son, to hear the instruction that causeth to err from the words of knowledge.

I know thy works, and thy labour, and thy patience, and how thou canst not bear them which are evil: and thou hast tried them which say they are apostles, and are not, and hast found them liars:

I have not written unto you because ye know not the truth, but because ye know it, and that no lie is of the truth.

And Jehoshaphat said, Is there not here a prophet of the Lord besides, that we might enquire of him?

They went out from us, but they were not of us; for if they had been of us, they would no doubt have continued with us: but they went out, that they might be made manifest that they were not all of us.

Wherefore laying aside all malice, and all guile, and hypocrisies, and envies, and all evil speakings, As newborn babes, desire the sincere milk of the word, that ye may grow thereby: If so be ye have tasted that the Lord is gracious.

Having a form of godliness, but denying the power thereof: from such turn away. For of this sort are they which creep into houses, and lead captive silly women laden with sins, led away with divers lusts, Ever learning, and never able to come to the knowledge of the truth.

For the time will come when they will not endure sound doctrine; but after their own lusts shall they heap to themselves teachers, having itching ears;

Take heed therefore how ye hear: for whosoever hath, to him shall be given; and whosoever hath not, from him shall be taken even that which he seemeth to have.