'Righteousness' in the Bible

If you know that He is righteous, you know that everyone also who practices righteousness is born of Him.

Little children, make sure no one deceives you; the one who practices righteousness is righteous, just as He is righteous;

By this the children of God and the children of the devil are obvious: anyone who does not practice righteousness is not of God, nor the one who does not love his brother.