What evidence do you have that the 'gnostics' were not believers?
The audience was a confused church in Asia. The pastor there asked John to write a letter to help clear up some major doctrinal heresy called "Gnosticism."
Gnosticism comes from the Greek word " gnosis", which means knowledge.
The Gnostics were a group of people who believed they possessed superior spiritual knowledge.
They believed that all flesh is evil and that only spirit is good.
Because they believed that, they didn't believe that Jesus really came in the flesh - they believed He was an illusion.
They also believed that because sin had to do with our flesh, there really wasn't sin - sin was also just an Illusion.
(That's similar to people today who believe sickness is an illusion.)
The church in Ephesus was filled with people who not only didn't believe Christ came in the flesh, they didn't believe sin was real.
Gnostics are not believers.