Antichrist and the last days

There is a warning offered here, not to be carried away by false-christs and false-prophets.
Obviously there were some in John’s day who were.
He calls them out in these verses…telling us that they may have acted like us, they may have behaved like us…but they weren’t truly one of us…or else they would still be here.
We have a warning to make our calling and election sure. To be careful that we are not carried away by these or the spirit of anti-Christ.