Albert Barnes' Notes on the Whole Bible - 1 John 5:19
And we know that we are of God - We who are Christians. The apostle supposed that true Christians might have so clear evidence on that subject as to leave no doubt on their own minds that they were the children of God. Compare 1 John 3:14; 2 Timothy 1:12.And the whole world - The term “world” here evidently means not the material world, but the people who dwell on the earth, including all idolaters, and all sinners of every grade and kind.Lieth in wickedness - “In the wicked one,” or under the... read more
The Pulpit Commentary - 1 John 5:19
Omit the "and" before "we know." There is no καί or δέ in the true text; and the asyndeton is impressive. The whole world lieth in the evil one. This is the second great fact of which Christians have certainty. They, as children of God, and preserved from the evil one by his Son, have nothing to do with the world, which still lies in the power of the evil one. That "the evil" τῷ πονηρῷ is here not neuter but masculine is evident from the context, as well as from 1 John 2:13 ,... read more