Revelation 2:13
“I know thy works, and where thou dwellest, even where Satan’s seat is: and thou holdest fast my name, and hast not denied my faith, even in those days wherein Antipas was my faithful martyr, who was slain among you, where Satan dwelleth.”
He that hath an ear, let him hear what the Spirit saith unto the churches; He that overcometh shall not be hurt of the second death.
And to the angel of the church in Pergamos write; These things saith he which hath the sharp sword with two edges;
I know thy works, and where thou dwellest, even where Satan’s seat is: and thou holdest fast my name, and hast not denied my faith, even in those days wherein Antipas was my faithful martyr, who was slain among you, where Satan dwelleth.
But I have a few things against thee, because thou hast there them that hold the doctrine of Balaam, who taught Balac to cast a stumblingblock before the children of Israel, to eat things sacrificed unto idols, and to commit fornication.
So hast thou also them that hold the doctrine of the Nicolaitans, which thing I hate.
Counter-Arguments
The strongest case that this verse does not belong in this theme.

Cross-References
“But if any man love God, the same is known of him.”
“I know thy works: behold, I have set before thee an open door, and no man can shut it: for thou hast a little strength, and hast kept my word, and hast not denied my name.”
“Nevertheless the foundation of God standeth sure, having this seal, The Lord knoweth them that are his. And, Let every one that nameth the name of Christ depart from iniquity.”
“If thou faint in the day of adversity, thy strength is small.”
“Behold, I come quickly: hold that fast which thou hast, that no man take thy crown.”