That's what reading Second John was like. Flew by in almost no time. But the words from John were almost the same as in First John.
Interesting that he writes to the "chosen lady." Could have been a lady, or the church at large – who knows (another question when I get to heaven). The amazing part is that his message is consistent. You have to know the truth to follow it. You have to live the truth ("love one another") if you say you are a believer. You have to slam the door on those who teach a lie.
Once again, without saying it, John's emphasis is on what we "know" or need to know. How can we know someone is a false teacher if we don't know the truth? How can we know the truth if we never take time to study it? At this stage in my life, I could not refute a false teacher of algebra, because that's not my specialty. But, if I had kept up with algebra and worked out several resolutions (answers) every day, I could probably point out a few bad algebra teachers.
So it is that John says again that the "church" (that's the body of believers or followers) need to beware of false teachers. To the point that we shouldn't even let them in our "house"!
There's more…stay tuned.