Parsons: A further issue I have always had with Christianity is the one you express as follows:
"Christians are enjoined by their faith to love others, and I take it that means that regardless of how badly a person has gone wrong, we think that, by the grace of God, that they could someday be brought to disconnect themselves from their sin by repentance."
Taken literally, this means that Christians are enjoined to love, say, people who throw acid into the faces of little girls to keep them from going to school. Indeed, Christians are enjoined to love tyrants, serial killers, traffickers in sexual slavery, drug cartel thugs, terrorists, fanatics, con men who cheat the elderly out of their life savings, etc.
This is one of the many cases where Christianity, by setting up an impossible (and undesirable) ideal creates conditions that guarantee self-deception and hypocrisy. CAN you love someone like, say, Syrian president Bashar al-Assad? SHOULD you even if you could? I think the answer to both questions is "no."
I submit that a person with any sense of decency who is well informed about the actions of Assad--shelling towns, sending death squads to massacre unarmed civilians, etc.--cannot love such an individual, not even "by the grace of God." If such a person claims to do so, I think that he is fooling himself or attempting to fool the rest of us.
Should you love Assad, even if you can? Why? Because of the off chance that he might someday repent? Get real. I submit that the proper, the MORAL attitude to take towards Assad and his vile ilk is one of outraged contempt.
VR: Sometimes this issue gets cast when Christians ask whether they ought to love Satan. For non-universalists, Satan is a spiritual hopeless case; there is no good for Satan that anyone can possibly hope for. Again, with some persons who do great evil, you it's hard to find anything in that person that could give you a basis for a movement back toward good.
For me, loving people like that is, as Obama would say, "above my pay grade." It's tough enough for me to maintain an appropriate loving attitude toward people who behave rudely on Dangerous Idea (of all persuasions). So, your question is better addressed to sa better candidate for canonization than yours truly. And to pretend that you have actually succeeded in loving people when you really haven't is worse than just hating their guts. Falwell makes a fool of himself, of course, when he pretends that he loves gay people.
There are remarkable transformations of evildoers, and it is a major theme in Christianity and literature. John Newton, the slave ship owner who wrote Amazing Grace comes to mind, and even from Star Wars there is the (fictional) transformation of Darth Vader at the end of Return of the Jedi.
I wonder if Bonhoeffer ever addressed this sort of thing. Did he think it was possible to love Hitler, and what could he mean by that given his involvement in efforts to kill him.