"Therefore, brothers and sisters, let us repent immediately.....For when they hear from us that God says, "It is nor credit to you that you love those who love you, but it is a credit to you if you love your enemies, and those who hate you," when they hear such things, they marvel at such extraordinary goodness. But when they see that we not only do not love those who hate us, but do not even love those who love us, they scornfully laugh at us, and the name (ie. God) is blasphemed."
This fragment from Second Clement doesn't need any commentary. Brother and sisters in Christ, let us love one another.