"During the US Civil War, hatred became entrenched between the North and South. In one instance, President Abraham Lincoln was criticized for speaking of benevolent treatment for the Southern rebels. The critic reminded Lincoln that there was a war going on, the Confederates were the enemy, and they should be destroyed. But Lincoln wisely responded, “I destroy my enemies when I make them my friends.”
Lincoln’s comment is insightful. In many ways it reflects Jesus’ teaching in the Sermon on the Mount: “I say to you, love your enemies, bless those who curse you, do good to those who hate you, and pray for those who spitefully use you and persecute you, that you may be sons of your Father in heaven” (Matt. 5:44-45).
We will encounter difficult people in our lives—some on whom we will need to set limits. But to give in to the temptation to undermine or hurt them in any way is not God’s way. Instead, we should pray for them, show consideration, look out for their best interests, and emphasize the positive. This may result in changing an enemy into a friend.
Not everyone will respond positively to us, but we can pray and plan for a more harmonious relationship. What difficult person can you start befriending?"
http://odb.org/2012/07/26/changing-enemies-into-friends/