This is how we know what love is: Jesus Christ laid down his life for us. And we ought to lay down our lives for our brothers.
If anyone has material possessions and sees his brother in need but has no pity on him, how can the love of God be in him?
Dear children, let us not love with words or tongue but with actions and in truth.
This then is how we know that we belong to the truth, and how we set our hearts at rest in his presence whenever our hearts condemn us. For God is greater than our hearts, and he knows everything.
1 John 3:16-20