Luke 6:27 But I say unto you which hear, Love your enemies, do good to them which hate you,
What a testimony of love! It's easy to love people you like because they don't do too much to make you mad or betray you. But when your enemy comes around, you have to rely on the love of Jesus in you. What better way to lead souls to Christ then by showing them love when they have done everything to make you not love them?
In retrospect, if you do not love your enemy then the Bible says that you don't even know God.
He who does not love does not know God for God is love.