Jesus gives John SEVEN messages that he has to write down and send to the 7 churches in Asia: one customized message to each of the SEVEN churches. These messages were not sent separately to the churches; all SEVEN messages were sent to all SEVEN churches!!!
At the end of each message, Jesus says: He who has an ear, let him hear what the Spirit says to the churches (Rev. 2:7). Listen carefully to all messages… There is a deeper meaning here…!