It shows that He caused you to be born again with the spiritual life His Son earned for us. Return once again to verse 5. Remember that, just as you received physical life entirely apart from your will, so also was spiritual birth given to you only because God eternally decreed to bestow it. There is that which we call natural love. After having fallen into sin, man can still have that.
Some people however can reveal bitter hatred.
There are those whom we can rightly call criminals, who spend a good part of their lives in prison. But the serious question is whether we and our neighbors have spiritual love. Now we are going to appreciate what God did for us through His Son and His cross and Spirit, if we hold on tightly to the truth which Paul wrote. The main question is not simply whether we hate the neighbor and treat him cruelly by word of mouth or hand. The deeper question is whether we hate God.