In Revelation, though there is an employment of a significant amount of apocalyptic imagery, much like in the prophetic works of the Hebrew Scriptures, this apocalyptic imagery is primarily designed to reveal what some may refer to as “spiritual” truths and activities that are at work and at play in relation to material and physical happenings.
Humans are limited in vision, and as Isaiah says, the Creator God’s ways and plans are not those of humanity, nor are His thoughts and deeds the thoughts and deeds of those that were created to bear His image (Isaiah 55:9). There is something of a veil that limits human vision, which keeps humanity from seeing what it is that the Creator God sees. The purpose of apocalypse (revelation) is to remove that veil, which is the very definition of the word.
For those that were understood to have been receiving communications from the Creator God through the Hebrew prophets in the centuries before Christ, and for those in the first century that were understood to have been receiving communications directly from Jesus through John the Revelator, this removal of the veil, in a world in which there were no separations between religious activities and so-called “secular” activities---no division between the sacred and the profane, the unveiling would be understood as the Creator God taking steps to condescending to reveal the spiritual goings-on that were related to what was happening in the world around them. This is dreadfully important for any potential understanding of words to be found within Revelation.
One must remember that Paul and Peter, along with the Hebrews author and the author of the letters of John, all wrote letters to specific churches and individuals. Though these letters would become useful to the whole of the church, they were first directed to and dealt with places, people, and events. Knowing this, one should exercise restraint when tempted to treat John’s communications differently. Just because a reader of Revelation happens upon fantastic and difficult-to-understand imagery, that certainly doesn’t mean that the same reader should dismiss John’s insistence that these letters, and this Revelation, are for the “seven churches that are in the province of Asia” (1:4a).
Returning then to the words of temperature (hot, cold, lukewarm), having insisted that they serve as geographic indicators, it is imperative to realize that they are something of a play on familiar words and of what is well-known about the area in which Laodicea is set. It should not be a surprise to find Jesus, through the author, employing such a strategy. Even the Apostle Paul’s famous phrase of “from faith to faith,” or “ek pisteos eis pistin” (Romans 1:17), is lifted from what could be termed as the liturgy of the Caesar cult.
In this, Paul takes a familiar term and applies it to what should be truly understood about Jesus, rather than Caesar. This is even more pronounced with the New Testament’s employment of the very word “gospel,” which was also in heavy and specific use within the Caesar cult, in application to the works of Caesar himself. So the New Testament has recurring instances of plays on words and the usage of familiar terms, re-worked and re-deployed for particular effect on a regular basis.