In 1 John 3:11 (written later than the gospel that bears his name) John says, “For this is the message that ye heard from the beginning, that we should love one another.” Years after Christ’s death, John, in writing the epistle, calls us back to Christ’s original command in John 13. Speaking to the church, John in effect says, “Don’t forget this. . . . Don’t forget this. This command was given to us by Christ while he was still on the earth. This is to be your mark.”
