Summary: Pergamos left the church door open to the world.
THE SEVEN CHURCHES OF REVELATION
PERGAMOS—THE WORLDLY, CORRUPTED CHURCH
TEXT: Revelation 2:12-17
Revelation 2:12-17 KJV 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.  Repent; or else I will come unto thee quickly, and will fight against them with the sword of my mouth.  He that hath an ear, let him hear what the Spirit saith unto the churches; To him that overcometh will I give to eat of the hidden manna, and will give him a white stone, and in the stone a new name written, which no man knoweth saving he that receiveth it.
I. INTRODUCTION—THE BATTLE WITH WORLDLINESS
-As I have contemplated this third church that our Lord Jesus Christ addresses through John, I have to remember some of the warnings in Scripture:
Jude 3-4 KJV Beloved, when I gave all diligence to write unto you of the common salvation, it was needful for me to write unto you, and exhort you that ye should earnestly contend for the faith which was once delivered unto the saints.  For there are certain men crept in unawares, who were before of old ordained to this condemnation, ungodly men, turning the grace of our God into lasciviousness, and denying the only Lord God, and our Lord Jesus Christ.
Matthew 13:25 KJV But while men slept, his enemy came and sowed tares among the wheat, and went his way.
Ephesians 4:14 KJV 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;
2 Peter 2:1-2 KJV 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.
-It is important to notice that the enemy uses people to work as decoys. He places the decoys into a setting of believers and then uses their leavening influence to corrupt the church.
Joby Warrick writes a harrowing story in Triple Agent about how a Jordanian physician who was radicalized on Islamic websites. This young physician would stay up late at night after his work in the daytime among the pediatric patients in Amman, Jordan and be infused with the vitriolic rhetoric of the Islamic preachers on You Tube until he wanted to get involved in the jihad. He did so after he was picked up by the Jordanian spy agency who found his online postings. They were going to attempt to send him into Pakistan as a spy but when he got there, he revealed why he was there. He told the jihadists that he was working for the Jordanians and had some connections to the CIA. Over a period of about a year, this young physician put on a suicide vest and made it into the CIA compound in Khost in Afghanistan and killed himself along with 9 other top CIA officers working in the Middle East. Once the investigation was done by CIA Director Leon Paneta, it was discovered that the CIA had let down their very high standards that they normally followed because they were so desperate to get Osama bin Laden and his top two lieutenants. The same thing happens to churches when they allow their guard to be dropped in pursuit of all sorts of so-called success.