Proverbs 10:12 Hatred stirs up strife, But love covers all sins.
Peter may have based his words on this proverb, but he had reason to. We need to depend on what God has taught us throughout time and not just the here and now.
God has shown us that there is a time for everything and that we will go through all facets of life; but love must continue throughout it.
Hatred builds up ill feelings within us and those come to the surface pretty quickly when we leave love out of the equation; it is so easy to hit out at someone when we have hatred inside of us.
But love will allow us to move forward and to show others just how awesome God can be!