“So the two chief characteristics of the false teachers are that they were troubling the church and changing the gospel. These two go together. To tamper with the gospel is always to trouble the church. You cannot touch the gospel and leave the church untouched, because the church is created and lives by the gospel. Indeed, the churches greatest troublemakers (now as then) are no those outside who oppose, ridicule and persecute it, but those inside who try to change the gospel. It is they who trouble the church. Conversely,
the only way to be a good churchman is to be a good gospel-man. The best way to serve the church is to believe and to preach the gospel."
The emphasis is mine, but it should be that of every minister besides