Affectionate parting caution.
From idols - Christians were everywhere surrounded by idolaters with whom it was impossible to avoid some contact. Hence, the need of being on their guard against an indirect compromise or communion with idolatry. Some at Pergamos, in the region whence John wrote, fell into the snare of eating things sacrificed to idols (Revelation 2:14). The moment we cease to abide "in Him that is true (by abiding) in Jesus Christ," we become part of 'the world that lieth in the wicked one,' given up to spiritual, if not in all places literal, idolatry (Ephesians 5:5; Colossians 3:5).