Behold, how great a love the Father has bestowed on us, that we should be called children of God! For this cause the world doesn't know us, because it didn't know him.
I love that verse. Behold, what manner of love God has bestowed upon you, that you should be called the son of God. What glorious love, that God should adopt me as His son, that God should claim me as His son. That God should call me His son. What manner of love God has for me that He would call me His son.