One of Jesus' most difficult teachings is for us to love our enemies and bless those who persecute us. This runs counter to every human instinct and cultural expectation since the world was created. And yet, it is exactly how God behaves toward us. As people to claim to follow Jesus, one of the most powerful witnesses we can have is in how we treat our enemies. If we seek to follow his teaching, we'll eventually find that in fact from God's perspective there are no enemies, only wounded and fearful people who need love. Perhaps we'll find the same.
In addition to scripture Living Without Enemies: Being Present in the Midst of Violence by Samuel Wells and Marcia A. Owen serves as a key supporting work.