The Seven Churches in the Book of Revelation

The seven churches of The Book of Revelation were 
located in the province Asia, that was in Turkey of today.

Jesus speaks of their spiritual condition. Conditions that are common in churches even today.

Only two of the churches,
Smyrna and Philadelphia worked well without serious problems.

Jesus has the seven stars (Rev 3:1a), which are symbols of the seven angels or the seven messengers of these seven churches, see also God's Throne in Heaven.

The following five churches had serious problems:

Ephesus:
They were intolerant of evil in the church. They couldn't tolerate those who called themselves apostles but weren't. They had suffered for Christ. (Rev 2:2–3,
1 Cor 5:12–13a, 2 Cor 11:4, 13). But they had forsaken their first love for God 
(Rev 2:4, 1 Cor 13:1–7). Jesus probably speaks both of their love for him and of their love for each other (1 Cor 13:3), see The Golden Rule in
The Sermon on the Mount. They needed to repent and do the works they did at first. Otherwise, God would come and take the lampstand out of its place (Rev 2:5).
The lampstand is a symbol of the church (Rev 1:20b). It probably means that the church would cease to exist if they didn't repent.

Pergamum:
They clung to the name of the Lord despite all the pagan worship that was going on there (Rev 2:13). What Jesus had against this church was that some of them hold to the following, see also The Parables of the Mustard Seed and the Leaven: 

• The teachings of Balaam, who taught Balak to entice the Israelites to sin by eating food sacrificed to idols and committing sexual immorality
  (Rev 2:14), see Balaam and Balak. Balaam taught them to introduce
  pagan worship that also involved immorality. It revolved around the idea of mixing the worship of the one true God with paganism.
• The teaching of the Nicolaitans (Rev 2:15) which essentially meant that
  the leadership in the church became increasingly exalted, and did all the thinking for the people in the church. This was contrary to what Jesus taught (Mat 20:25–28), see the last part of The Book of John. 

They needed to repent (Rev 2:16).

Thyatira:
Some of them grew in their faith and their work showed it (Rev 2:19). What Jesus had against this church was that they tolerated the woman Jezebel, who called herself a prophetess, who taught and seduced God's servants to practice sexual immorality and to eat food sacrificed to idols, and she wouldn't repent 
(Rev 2:20–21). Probably it was about compromising by participating in pagan festivals. Pagan unbiblical rituals entered the church. Those who committed adultery with her must repent of her deeds  (Rev 2:22). Jezebel in the Old Testament was the woman behind the worship of Baal and Asherah on a national scale in Israel
(1 Kings 16:31-33), and is an image of this woman. 

Sardis:
It had the reputation of being alive, but it was dead (Rev 3:1b), meaning that the Holy Spirit wasn't working in the church. It appeared to be alive but wasn't,
it worked in the flesh. They needed to remember what they had received and heard, to retain it and repent (Rev 3:2–3), see the following:

1. Wake up, see The Parable of the Wise and Foolish Virgins.
2. Strengthen what was left.
3. Remember what they hat read and heard, see The Four Gospels.
4. Obey, begin to walk in obedience, see Sanctification.
5. Repent, change direction and turn back to the Lord.

But a few people in the church still followed Christ (Rev 3:4–5).

Laodicea:
The members of this church were lukewarm (Rev 3:15–16). It's easier to reach a person with the gospel who has a cold heart than one who has a lukewarm heart.
A lukewarm person doesn't understand that he or she is a sinner (Rom 3:23, 
1 John 1:8–10). They thought they were rich, that they had prospered and needed nothing, not realizing that they were wretched, pitiable, poor, blind, and naked 
(Rev 3:17). It's their spiritual condition. They can't see their true spiritual state.
Lukewarm persons may have a form of godliness but deny it's power (2 Tim 3:1–5). They must become zealous for God and repent (Rev 3:19). They needed forgiveness from sin and to be saved (Rev 3:18, Isaiah 61:10). See time 16:54–19:50 in
Luke 4 (Part 2) :16-30 • Jesus, the fulfillment of Prophecy.

The following two churches worked well:

Smyrna:
They were greatly persecuted until death. Jesus knew about their afflictions, their poverty, and the slander they were subjected to (Rev 2:9–10a). By being faithful unto death they would receive the Crown of Life (Rev 2:10b, Mat 5:10–12,
Luk 12:4).

Philadelphia:
Jesus had opened a door for them, which no one could close, so that they could reach out with the gospel (Rev 3:8a, 1 Cor 16:9). Even so, they had little power, they had kept God's word and hadn't denied the name of Jesus (Rev 3:8b).
They should hold fast what they had in Jesus, so that no one could take their crown (Rev 3:11b).

These seven churches have also been given a historical–prophetic view:

• Ephesus ("desired") – Apostolic church (AD 30–100).
  False apostles were the biggest issue to deal with at that time.
• Smyrna ("myrrh") – Persecuted church (AD 100–313).
  The church had entered a time of incredible persecution.
• Pergamum ("thoroughly married") – State church (AD 313–590).
  Roman emperor Constantine the Great was the first emperor to convert
  to Christianity. 313 AD tolerance for Christianity was declared.
  When the state begins to rule the church, it becomes corrupt, as it becomes advantageous to profess Christianity for political reasons.
• Thyatira ("perpetual sacrifice") – Papal church (AD 590–1517).
  It was an amalgamation of Roman Catholicism and paganism.
• Sardis ("those escaping") – Reformed church (AD 1517–1730).
  While the Reformation under Martin Luther was considered good in
  many ways, it also stands as an effort that didn't quite go far enough.
  It didn't go all the way to biblical Christianity, but it made the Bible accessible to ordinary people. It opened the doors for missionary work
  in the next period, where it produced incredible evangelists.
• Philadelphia ("brotherly love") – Missionary church (AD 1730–(1900)).
  This was the period when the church enjoyed unprecedented freedom of movement to go to the ends of the world to share the gospel. There are many believers who believe that this missionary period is still ongoing and will continue until Jesus returns (Rev 3:10), meaning that this period and the next period will exist for the same time.
• Laodicea ("people ruling") – Apostate church (AD 1900–).
  The church will largely become apostate during this period (2 Tim 3:1–5). This doesn't mean that every believer will then be an apostate 
  (2 Thess 2:3).

Each of these churches, which were true churches at that time, represent different time periods of the Body of Christ throughout the ages of church age history, from its birth in the Book of Acts until the return of Christ. The titles of the churches tell us about the most  prominent characteristics of these time periods. Note that God always have had a remnant of people who followed him during these time periods. People who throw off traditions and rules of man and come back to the word of God.

See also The Book of Revelation.