Expositor's Bible Commentary Commentary 1 John 3:10

"In this the children of God are manifest, and the children of the devil: whosoever doeth not righteousness is not of God, neither he that loveth not his brother." — 1 John 3:10 (ASV)

This verse reveals the heart of the entire section and furnishes a transition to the next one. John is not concerned with a theoretical consideration of the nature of sinfulness or the possibility of sinlessness but the issue of the community. How are the children (community) of God to be recognized and how are the children (community) of the devil to be discerned?

“Anyone who does not do what is right is not a child of God.” And what is the “right” he does not do? He “does not love his brother.” “Love for one’s brother” is the true test of righteous behavior. This requirement of love helps explain the absolute requirement that those who are born of God “cannot go on sinning” (vv.6, 9). For if God is love, and if he lives in us and we in him, then love for fellow believers will occur as an expression of righteousness without exception.

The author, then, is not stressing absolute moral conformity or “sinless perfection” but the one requirement by which all other requirements are measured—love for one’s fellow Christian. For this there is no substitute, its violation allows for no excuse, its application permits no compromise. Here there are no gray areas, no third possibilities. We either love our fellow believers and prove we are God’s children, or we do not love them and prove we belong to the devil.