Acts 20:30

And as they did eat, he said, Verily I say unto you, that one of you shall betray me. And they were exceeding sorrowful, and began every one of them to say unto him, Lord, is it I? And he answered and said, He that dippeth his hand with me in the dish, the same shall betray me. The Son of man goeth as it is written of him: but woe unto that man by whom the Son of man is betrayed! it had been good for that man if he had not been born. Then Judas, which betrayed him, answered and said, Master, is it I? He said unto him, Thou hast said.

Holding faith, and a good conscience; which some having put away concerning faith have made shipwreck:

And their word will eat as doth a canker: of whom is Hymenaeus and Philetus;

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;

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. And many shall follow their pernicious ways; by reason of whom the way of truth shall be evil spoken of. And through covetousness shall they with feigned words make merchandise of you: whose judgment now of a long time lingereth not, and their damnation slumbereth not.

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.