Idolatry

1 John 5:21
“Little children, keep yourselves from idols.”

“In ending with this verse, John is doing something that is very characteristic of himself. We have seen repeatedly his liking for contrast – light and darkness, love and hate, true and false. John was also fond of negatives. He generally put his positive first and then his negative. This is what he does here:

‘This is the true God and eternal life. Little children, keep yourselves from idols.’

To put it yet another way, John always warns us. John also never wrote this letter merely to give knowledge as such. He wanted to help these people. He is as practical as this: ‘Little children, keep yourselves from idols,’ as his last words. ‘Keep yourselves,’ says John. We must guard ourselves as if we were in a garrison. “Work out your own salvation with fear and trembling, for it is God which works in you’ (Phil 2:12-13)”