John circles back to the “little children,” those who are NEW to the faith. He sets the urgency of the hour with two critical lessons for the church: It’s “the last hour” & the signs of “the last hour.” He warns for the Antichrist and also many Antichrist. But He’s warning the church to not be deceived by those who are claiming Christ, but are lying with their lifestyle. Because when doctrine is discarded or relationships are broken off in unbiblical ways, you can be sure there’s an ungodly person (An apostate) in your midst.