14 "To the angel of the church in Laodicea write: These are the words of the Amen, the faithful and true witness, the ruler of God's creation.
15 I know your deeds, that you are neither cold nor hot. I wish you were either one or the other!
16 So, because you are lukewarm — neither hot nor cold — I am about to spit you out of my mouth.
17 You say, 'I am rich; I have acquired wealth and do not need a thing.' But you do not realize that you are wretched, pitiful, poor, blind and naked.
18 I counsel you to buy from me gold refined in the fire, so you can become rich; and white clothes to wear, so you can cover your shameful nakedness; and salve to put on your eyes, so you can see.
19 Those whom I love I rebuke and discipline. So be earnest, and repent.
20 Here I am! I stand at the door and knock. If anyone hears my voice and opens the door, I will come in and eat with him, and he with me.
21 To him who overcomes, I will give the right to sit with me on my throne, just as I overcame and sat down with my Father on his throne.
22 He who has an ear, let him hear what the Spirit says to the churches." NIV
The Roman province of Asia included more churches than these seven. Why did John single them out?
One theory is that these seven cities may have been centers of seven postal districts. These seven churches all stand on the great circular road which formed a rough circle around the west central part of the Roman province of Asia. As such, these seven sites served as good centers of communication for the surrounding districts. Letters in the first century had to be handwritten, and a letter sent to one church would be passed on to be read by Christians in other congregations.
The letters to the seven churches called for the Christians to repent of sin and return to faithfulness and good works; encouraged them to stand firm for Christ against the temptations, trials, and persecutions of the Roman Empire; and promised specific rewards to the martyrs who faced death without denying Christ.