“The one who does not love does not know God, because God is love.”
First, “love is from God.” (1 John 4: 7) Love does not and never has and never will originate in us. In our natural state, our fallen state, we are incapable of producing love. “Love consists in this: not that we love God, but that He loves us.” (1 John 4: 10)
I repeat this: Love is not from us; rather, love originates in God. “We love because He first loves us.” (1 John 4: 19)
Because love emerges directly from God, “there is no fear” in this love. “Instead, perfect love drives out fear.” (1 John 4: 18)
What have we to fear since God is for us? Who is able to condemn us since God justifies us? Because God is on our side and because He justifies us, we are to “love the one born of [God.]” (1 John 5: 1) How can we condemn our brothers and sisters when God sets aside His condemnation of us? How can we hate one another when God puts His hatred of the sin in us upon His Son?
“The one who loves God must also love his brother.” (1 John 4: 21)