1 John
2:5
but whoever keeps his word, in him truly the love of God is perfected. By this we may know that we are in him:
3:1
See what kind of love the Father has given to us, that we should be called children of God; and so we are. The reason why the world does not know us is that it did not know him.
3:10
By this it is evident who are the children of God, and who are the children of the devil: whoever does
not practice righteousness is not of God, nor is the one who does not love his brother