Writing status: This is a little out-of-hand and probably raises some questions I'm not aware of.
The moral circle is the set of all beings to which we consider ourselves to have moral obligations. Something can be inside, or outside, one's moral circle, a member, or not, of the set of beings to which we consider ourselves to have moral obligations. The reason for why something belongs in the moral circle is because it has feelings, especially that it suffers, in such a way that we need to respond to its circumstances. Generally, we need to respond when something threatens a feeling being's well-being. (This is how "moral circle" is generally used, and that is how I'll be using the concept in this post. Conceivably, we could have moral obligations for other reasons.)
As we come to really take into account the existence of feeling beings, we include them in our moral circle. So for instance, we might consider that the impairment of well-being that happens in distant countries of people we will never know personally is just as bad as that which happens to us or to people we care about personally, in our own lives. Therefore, if we are morally obligated to help the people in our own lives, we should help the people far away if we can, all things being equal.
A Christian could counter-argue that righteousness comes by faith, and that the point of the gospel is that it is not you who save yourself by your works, but rather God who saves you by his grace. It could be argued that to a Christian, moral obligation does not exist. We live in the freedom of being covered by Jesus' blood, shed on the cross.
Is it really Christian to say "I don't have to worry about anything in secular ethics. I don't rely on reason. I rely on grace. I am OK."?
It may be the case that salvation is only by grace, apart from works. I think this is an area that is nuanced. Perhaps forgiveness of sins is by grace, but repentance is up to us. I think that makes sense, and maybe I will find that the Bible supports it, when I do another study of the Bible to check against the religious philosophy I've been working on. I think something like that is what the New Wine System teaches, according to its developer.
But I will grant for the sake of argument that perhaps grace saves, and "saves" means "does everything that it takes to give a person eternal life". In that case, if your only concern is salvation, then great. As soon as you do whatever it is you need to in order to receive that grace (or even, nothing at all, if that's all that's required), then you can live your life as you please. You can be as moral as you feel like, and no more moral than is reasonable, in your eyes.
You certainly care about your own well-being. You are covered by grace, and have received the gift of salvation, in which you rest. But do you love God? Do you have the same heart as he has for people? Can you love someone without caring about what they care about? If you're the kind of person who only cares about your own salvation, do you think God is pleased with you? Do you think God can leave you in that state? So God will eventually teach you to care like he does. If grace saves, then you were always saved. But God will make you care like he does.
Does God love you? Does he love people far away? If he loves you, why not people far away? Are you better than them, more deserving of a life of comfort and wealth than they are? It's true that there is some nuance to this. The material wealth of the West isn't all it's cracked up to be. Material wealth doesn't always make life better. And a certain amount of impaired well-being is an acceptable part of life. But some people suffer so much for being poor that there isn't really that much nuance in their case. Suffering itself beyond a certain threshold is impaired well-being, and God suffers with their suffering, just as he does with yours. If you can alleviate your own suffering, you tend to do that. So why not alleviate others' suffering? You love God by alleviating your own suffering, and you love him by alleviating that of distant people. This is the love of a healer healing, or a servant washing someone's feet.
So far, I haven't brought up the Bible. I can't provide a rigorous survey right now of the Bible's teachings on economic sin. But I can give some basic thoughts that are suggestive. In general, I know that many references to caring for the poor can be found in the Bible. The Old Testament prophets talked about that. Also in the New Testament, James speaks strongly against people who hold onto their wealth, causing the deprivation of those who work for them. One could say that James is no better than Paul, who says "salvation is by grace through faith, apart from works", but then, is Paul any better than James? I don't think that "salvation is by grace through works" means "we don't need to do the right thing" (not even Paul believed that), but if "grace" is taken to mean "we don't need to do works", then supposing that we need the words of Jesus to settle the dispute we might see between James and Paul, what does he say?
25 Behold, a certain lawyer stood up and tested him, saying, "Teacher, what shall I do to inherit eternal life?"
26 He said to him, "What is written in the law? How do you read it?"
27 He answered, "You shall love the Lord your God with all your heart, with all your soul, with all your strength, and with all your mind; and your neighbor as yourself."
28 He said to him, "You have answered correctly. Do this, and you will live."
29 But he, desiring to justify himself, asked Jesus, "Who is my neighbor?"
30 Jesus answered, "A certain man was going down from Jerusalem to Jericho, and he fell among robbers, who both stripped him and beat him, and departed, leaving him half dead. 31 By chance a certain priest was going down that way. When he saw him, he passed by on the other side. 32 In the same way a Levite also, when he came to the place and saw him, passed by on the other side. 33 But a certain Samaritan, as he traveled, came where he was. When he saw him, he was moved with compassion, 34 came to him, and bound up his wounds, pouring on oil and wine. He set him on his own animal, brought him to an inn, and took care of him. 35 On the next day, when he departed, he took out two denarii, gave them to the host, and said to him, 'Take care of him. Whatever you spend beyond that, I will repay you when I return.' 36 Now which of these three do you think seemed to be a neighbor to him who fell among the robbers?"
37 He said, "He who showed mercy on him."
Then Jesus said to him, "Go and do likewise."
The people in Jesus' audience in 1st-century Palestine couldn't have been held accountable for people in the New World, and perhaps not for people in China. But nowadays, we can encounter people who are distant from us. We hear that they are metaphorically lying by the side of the road, and we can choose to be neighbors to them, or not. Do we want to do what Jesus said? Do we care what he thinks and feels? You could argue that technically, the priest and the Levite could have inherited eternal life, because the man by the side of the road was someone they didn't have to be a neighbor to, so he wasn't. But if we are to love God with all our beings, as Jesus and the lawyer agreed were the way to eternal life, then we have to be interested in what Jesus wanted.
It's interesting to note that the lawyer thinks (and Jesus doesn't contradict) that to do good to someone is to show mercy to them. Altruism can have different psychological fuels, like how you can have a gas stove, or a wood stove, which itself can burn different kinds of wood. If we have mercy, when we recognize that the people around us do not love like Jesus wanted us to love, and that we do not either, we do not judge.
At the same time, if we want eternal life, we need to love God and love our neighbors as ourselves. These commands are ones that we ourselves can keep, if we have time. So the New Wine System teaches that we have time in which to learn after death, before we are brought before God to be with him forever. Someday we must become the kind of people who really do have the heart of God.
Some might say things changed at the cross, though. Maybe much of Jesus' teaching can be set aside, since he taught it to people before his death. Once he died, his death covers our sins, so we no longer need to take his living words as literally. How much actually changed at the cross, though? Consider these two passages from Matthew:
Matthew 5 (Jesus speaking):
17 "Don't think that I came to destroy the law or the prophets. I didn't come to destroy, but to fulfill. 18 For most certainly, I tell you, until heaven and earth pass away, not even one smallest letter or one tiny pen stroke shall in any way pass away from the law, until all things are accomplished. 19 Therefore, whoever shall break one of these least commandments and teach others to do so, shall be called least in the Kingdom of Heaven; but whoever shall do and teach them shall be called great in the Kingdom of Heaven. 20 For I tell you that unless your righteousness exceeds that of the scribes and Pharisees, there is no way you will enter into the Kingdom of Heaven."
And Matthew 22:
34 But the Pharisees, when they heard that he had silenced the Sadducees, gathered themselves together. 35 One of them, a lawyer, asked him a question, testing him. 36 "Teacher, which is the greatest commandment in the law?"
37 Jesus said to him, "'You shall love the Lord your God with all your heart, with all your soul, and with all your mind.'" 38 This is the first and great commandment. 39 A second likewise is this, 'You shall love your neighbor as yourself.' 40 The whole law and the prophets depend on these two commandments."
Jesus says, in Matthew 5, that there is a law that lasts until heaven and earth pass away (which means, we are still under it). Is this the law of Moses? Or is this the law of loving God with all your being, and your neighbor as yourself? This might be hinted by the Matthew 22 quote. Or is it some other law?
It seems like another candidate might be "profess to be a Christian and approve of the people in your life". Grace says "You aren't any better than anybody else -- you need grace -- so approve of other people. And faith is how you're saved -- just think that you trust God, and you do." That sort of sounds like it's a subset of "love God with all your being and love your neighbor as yourself". Certainly disapproving of people can hurt people sometimes.
Note that the "profess and approve" (arguably grace-and-faith-based) formula does fairly well with leading you to love your neighbor as yourself, but not as well with leading you to love God with all your being. The profession is only a beginning compared to loving God with all your being.
Because "profess and approve" is easier, it's popular, and the kind of thing people like to believe. It's an easy way to get people to like you. Just say "Let's go easy on each other and ourselves and approve of each other, professing faith in God", and you are more likely to make friends than if, among your prosocial "love your neighbor as yourself" (which might win you some popularity points, since it causes you to benefit people), you also say "love God with all your being". "Profess and approve" is a version of Christianity that the universal culture would select for. (To the extent that "love God with all your being and your neighbor as yourself" is popular and selected for, it tends to downplay loving God in any way that threatens to take away from human well-being, and so it tends to be a different flavor of the same appealing-to-humans thing.)
But the law that lasts to the end of heaven and earth that is actually offered by Jesus might be "love God with all your being and love your neighbor as yourself", but he did not set up the "profess and approve" law (or the "love God with all your being which means nothing other than loving your neighbor a lot" law). He didn't want us to judge, and yet he himself did not approve of everyone and everything. He told people he was being kind to to stop sinning. Professing allegiance to Jesus certainly counts for something, and something like approving of other people (not judging them, as Jesus commanded) also counts for something, and they could be considered part of the "love God with all your being and your neighbor as yourself" law. They are an entry point to the bigger and fuller law of love. (And so can the "love people" laws that are used as substitutes for "love God with all your being and love your neighbor as yourself".)
Many people, among those who "profess and approve" and those who "love people", if asked, would identify as those who love God. If we identify as those who love God, then why shouldn't we care about how he feels about his other children? To live up to our calling as lovers of God -- as children of God -- we should care about people who live far away from us. There are practical limitations to our ability to help people far away, but they are not absolute, and within them we should do something.
However, is this exactly the same thing as "expanding the moral circle" in a secular sense? Is this really moral obligation, and is this something done as a response to the impaired well-being of another feeling being? In Jesus' parable of the Samaritan helping someone he runs into on the side of the road, the action taken is definitely in response to the injury of a feeling being.
As to moral obligation, if we want eternal life, we must obey God's commands to love. You could look at that as moral obligation -- "we must" -- or not -- "we must only if we want eternal life and" -- presumably -- "we want God's approval" -- he set up the incentive to make things be the way he wanted them. But God's approval is the approval of legitimacy itself, and what is required to satisfy legitimacy is morally obliged, since morality is what legitimacy wants.
We find ourselves unwilling to say "thus says God" in moral areas (rely on God's commands to love as the foundation of moral obligation) and tend to rely on secular morality instead. Maybe it sounds overbearing to bring God into the picture. So instead we rely on the secular psychology of morality that relies on instinct and social pressure to produce feelings of moral obligation. But with God as the basis of moral obligation, there can be such a thing as realistic absolute standards -- grace allowing for the attainment of uncompromising holiness. Whereas, godless morality throws out wild absolutes with no way to live up to them -- so people become moral anti-realists. God, who is legitimacy itself (/himself), the truth, requires us to be aligned with him -- being aligned with legitimacy is itself to have fulfilled moral obligation. So I think we are morally obligated due to other's impaired well-being, but that moral obligation doesn't work the same in the context of God, as in the context of godlessness.
What about non-human animals? Extending the moral circle to non-human animals makes sense from a secular perspective. Materialists tend to want to do that, because animal brains aren't sufficiently different from ours in most (or all?) cases for us to think that they don't suffer consciously. From an immaterialist standpoint, we may think that animal bodies that appear before us only appear to have consciousnesses (similarly, we may think that other people are only p-zombies). But ordinaristically, we see that people are conscious and so are non-human animals. Even if we are sticklers for immaterialist ontology, ignoring the ordinary, we should have uncertainty that non-human animal bodies do not have animal consciousnesses associated with them, in the way that each of our own bodies are associated with each of our consciousnesses. This uncertainty should keep us from disregarding them as feeling beings.
Similarly, it makes sense to have some sense of uncertainty that artificial intelligences that behave sufficiently like humans are not conscious.
But what does the Bible say? There's nothing in the Bible about artificial intelligences, unless you expand what you mean by that to include organizations and states, which do not seem to be regarded as having personhood in a literal sense (although they can in a symbolic sense, as in prophecy). As to animals, again, this is not an exhaustive survey, but in Jonah 4, it says:
This lends some weight to the thought that God cares about animals. From Jesus (Matthew 10):
10 Yahweh said, "You have been concerned for the vine, for which you have not labored, neither made it grow; which came up in a night and perished in a night. 11 Shouldn't I be concerned for Nineveh, that great city, in which are more than one hundred twenty thousand persons who can't discern between their right hand and their left hand, and also many animals?"
29 "Aren't two sparrows sold for an assarion coin? Not one of them falls to the ground apart from your Father's will. 30 But the very hairs of your head are all numbered. 31 Therefore don't be afraid. You are of more value than many sparrows."
God cares more about humans, but vs. 31 wouldn't be as reassuring if we thought that God didn't care about the value of sparrows at all.
Why might God care about animals, but not as much as about humans? I'm not really sure. One possibility is that humans are sons and daughters of God, while animals are no more nor less than animals. God is more akin to us than he is to animals (the Bible says that we are made in his image, but does not say this of non-human animals).
I have thought before that animals may be persons -- do I think they are persons in the full-fledged sense that we are? In the sense that we say "I think, therefore I am", the way that we know ourselves as people, the full meaning behind the "I" that we speak there? Or are they only persons in the sense that they are consciousnesses with wills and preferences? Is there a difference between the latter and the former? If there is, then animals can still suffer, trust and have their preferences thwarted, and yet not be full persons.
Animals may not have free will in the same way that we do, at least to the extent of not being capable of moral reasoning, and thus are not capable of really loving God, really choosing him, or any other being, for that matter. When animals love, they have no choice, perhaps. It is also possible to look at lives and persons as different in terms of valuing them. So it's valuable to God to make animal lives go well (e.g., not be unremitting suffering), but animals themselves, as persons or proto-persons, are not as valuable. (The contents of these last two paragraphs are speculations that I may revisit later.)
From all this, I feel somewhat safe saying that the Bible supports eliminating gratuitous animal suffering, such as that caused by factory farming or cruelty to animals. We have enough uncertainty about whether God cares about animal suffering (importantly, it's hard for us to rule out that his care does not include caring about their suffering) that in cases where we don't really need to cause animal suffering, we shouldn't.
Finally, it is important for Christians to include God in their moral circle. This is part of loving God with all our being. God has well-being. The Scriptures say that he has emotions, which have been negative in response to events on earth, and our time is no exception. So we have a reason to care about him, in himself. But we tend to forget this.
One possible reason for this is that among Christians there are two opposing ideas (or ideas like one or the other of them): one, that we should adjust ourselves to fit God because he is perfect (and he is perfect according to a human idea of what perfection is -- he is all-great and thus can't have any kind of need by which we could benefit him); and the other, that God exists primarily to serve human well-being, or that human well-being was always truly what God wanted (and well-being is to be understood according to a human understanding of well-being), therefore we have no need to inquire into God's well-being, since God's well-being, if it exists, is identical with ours as we understand it (and perhaps we would also want to include the rest of creation to be considered with us -- plants, and animals, and so on). We can see the influence of these two ideas, or ideas like them, in various parts of Christianity, and perhaps there are not so many who are free from both of them.
If God is part of our moral circle, we might have to change to adjust to that fact, just as how the inclusion of distant people into our moral circle can change our lives.