Let all who have ears give heed to what the Spirit is saying to the Churches (Revelation 2:7,11,17, 29, 3:6, 13, 22).
Since we are now living in the end time, just prior to Christ's second coming, it behooves us to study and understand each of the messages God gave to Revelation's churches. John, the last living apostle of Jesus Christ, wrote Revelation in 95 A.D. on the island of Patmos. The visions he received applied, at least in part, to churches that existed in Asia Minor. However, their main application and thrust was for the End Time.
The church living in Ephesus received a personal message from Jesus, who "walked" or made his presence known among the churches. He knew their hard work and their unwillingness to put up with those who teach false doctrine or who want to be considered important in the church (Revelation 2:2).
Those, both then and now, who have an Ephesian-like attitude work spiritually hard and do their best to keep those who promote false doctrinal teachings out of their fellowship. They do, however, have a flaw that Jesus said required immediate attention.
But I do have something against you! And it is this: You don't have as much love as you used to (Revelation 2:4).
Although the church had an initial burning love for the Eternal and his truth, they became a bit complacent and let it fade. Jesus gives them a serious warning to return to the same kind of love they initially possessed or else he will not 'walk' among them and they will no longer be considered one of God's churches (Revelation 2:4 - 6).
Smyrna's church
I know your works and tribulation and poverty (but you are rich), and the blasphemy of those who declare themselves to be Jews . . . the devil is about to cast some of you into prison . . . (Revelation 2:9).
In the Roman area of Asia Smyrna was considered one of Rome's principal cities. It competed with two other nearby cities to be the chief city in Asia itself. It did not become important until a new foundation was laid by Alexander the Great.
Some of the brethren of the city did (and in the future will) suffer trials and troubles, and be placed in prison for a period of several days. Jesus wants and requires us to be loyal to him even as death for our beliefs approaches.
To the church in Pergamos
Pergamos (also known as Pergamon) was first populated by Greek colonists. As early as around 420 B.C. the city began to produce its own coinage. Lysimachus, who as King ruled Pergamos and the surrounding area from about 306 to 281 B.C., is said to have deposited in the city 9,000 talents of gold (the weight of which is equivalent to 675,000 U.S. pounds).
I know your works and where you dwell, where the throne of Satan is; but you are holding fast My name . . . (Revelation 2:13).
The church in Pergamum did not fear being labeled as 'Christians,' a designation that likely first came into use as a term of derision. They stayed true to God even though they lived in a place where the Roman Empire instigated its first murder of a Christian (Antipas - verse 13) due to his beliefs (Stephen, the first martyr for Christ, was stoned by religious leaders - Acts 7).
There church, however, had a giant problem. Some members were practicing what was taught by Balaam, an ancient prophet who got Israel to sin through them eating food offered in idolatrous worship and by becoming sexually immoral (Revelation 2:14 - 15).
Pergamos was considered the chief center of religion in Rome's province of Asia. It boasted at least three temples dedicated to the worship of the Roman Emperors as gods. It also was the location of a great altar dedicated to the pagan gods of Olympus and its chief deity Zeus. It is therefore no wonder that the church had to combat a very strong influence of Satan through the many false religions.
Some in the church sadly did succumb to the pressure and began to adopt pagan practices that were against God and what the Bible taught. Christ stated, in no uncertain terms, that unless those in the Pergamos church repented of compromising his truth that he himself would fight them (Revelation 2:16).
To the believers in Thyatira
Thyatira, known for its expertise in dyeing, was also a hub in trading indigo. Although Jesus praises them for their works (Revelation 2:19) a serious spiritual problem needs addressing. Within their midst is a woman who considers herself a prophetess. She is teaching God's people to commit fornication and to eat things the word of God forbids (Revelation 2:20).
Thyatira's difficulties were self-inflicted. They accepted the false doctrines of a female who believed she spoke for God. In reality, however, she was as evil as Jezebel, the wife of Israel's King Ahab.
It was not that Jezebel was necessarily seeking the utter destruction of the church in Thyatira. She seems to have been wanting to be seen as someone who was a great teacher. The fact was, however, that she promoted compromises with idolatry and with the truth in general.
Alive but dead in Sardis
Sardis, one of the oldest and most important Asia Minor cities, was the ancient capital of Lydia's kingdom until around 549 B.C. In 334 it surrendered to Alexander the Great, who gave it brief independence until it was conquered by Antigonus (one of Alexander's generals).
I know what you are doing. Everyone may think you are alive, but you are dead. Wake up! You have only a little strength left, and it is almost gone. So try to become stronger. I have found that you are not completely obeying God. (Revelation 3:1 - 2).
We find in the church at Sardis only a scant few Christians who have not compromised and spiritually defiled themselves. The church thinks it is alive and that it is a viable, active fellowship. In reality, from God's perspective, they are almost completely dead.
Those who have a Sardis-like attitude of false self-contentment with their lives as Christians are warned they must stop being spiritually lethargic and repent (Revelation 3:5 - 6).
To the church in Philadelphia
I know your doings. I have put an opened door in front of you, which no one can shut; because you have but a little power, and yet you have guarded My word and have not disowned Me (Revelation 3:8).
In 189 BC King Eumenes of Pergamon started the city, naming if after his love for his successor brother Attalus. Those that possess a 'Philadelphia' attitude are offered protection by God from the End Time persecution that will soon come to the entire world.
To the Laodiceans
I know what you have done; I know that you are neither cold nor hot. (Revelation 3:15)
Founded on seven hills, Laodicea was an important Asia Minor city. It was located along a popular trade route, which lent to its economic prosperity. The city made its own coinage, the inscriptions of which show evidence of the worship of Zeus and others.
The church in Laodicea is not cold (a totally dead church) nor hot (zealous for God and his truth). It just simply exists. The Laodiceans are not faithful or unbelieving. Their indifference to the truth of the Bible is what makes Jesus sick. They are given one last chance to repent . . . or else.
It behooves us to listen to the words of correction our Savior gave to the seven churches of Revelation. If we take his words to heart, and try our best to live by them, we will be rewarded as Jesus promised.