In this trilogy of articles I shall be highlighting the key features of an appropriate Christian response to the shooting in Christchurch. My first article shall focus on the victims; my second article on the perpetrator; and my third and final article on the problem of evil. Overall my concern shall be to show that Christianity provides a map to understanding and preventing human evil and is also able to meet the philosophical challenge presented by its occurrence.
1. Christian Teaching Illuminates the Connection between Hatred and Violence
In 1 John 3:15, we find these strange and startling words: “Whoever hates his brother is a murderer and you know that no murderer has eternal life in him.” The verse does not stand alone. It fact, it is a paraphrasing of Jesus’ own teaching in Matthew 5:21-22 where insulting or even being angry at others is set next to murder in terms of moral seriousness. 
On its face, all this sounds like an absurd exaggeration. On what reasonable assessment is an insult, let alone an unkind thought, approximately equivalent to murder? But Jesus’ teaching actually demonstrates his profound knowledge of human moral psychology; knowledge which helps to illuminate the specific causal mechanism by means of which hatred in thought and speech can escalate to violence—so salient a feature of the tragedy in Christchurch.
To properly understand this we need to first consider how people develop a moral character. Richard Swinburne, the Oxford professor of Philosophy, is helpful here. Humans are so made, he says, that when we freely choose to do good, it becomes slightly easier to choose to do good again at the next opportunity; and when we freely choose to do evil, it becomes slightly easier to choose to do evil again at the next opportunity. In this way, over time, we strengthen and weaken desires of various kinds and so form our moral character.   This is a view that goes right back to Aristotle (“A man becomes brave by acting bravely, just by acting justly”) and appears to be confirmed by modern neuroscience. 
Murder, I therefore suggest, cannot be adequately explained by proximate causes—malice, motive, means. It needs to be traced upstream to its point of origin: A secret unchecked fear or hatred that may have gestated for decades before culminating in actual violence. And while I hasten to add that hatred is not a sufficient condition of violence, it is a necessary condition: Not every unchecked hatred leads to a massacre, that is, but every massacre begins with an unchecked hatred. It is therefore wisdom, and not prudishness, which moves Jesus to warn us so solemnly against unkind thoughts and words. In front of the man who indulges even petty hatred opens a path which, should he continue along it, terminates in suffering, bloodshed and sorrow.
2. Theism in General, and Christian Theism in Particular, Provides the Most Coherent Metaphysical Framework within which to Affirm the Dignity of Persons and Condemn Hatred and Violence
To understand this, first note a precept familiar to every theologically literate Christian. The universe is not like a house which God built and from which he can then withdraw his attention. Rather, the universe and its inhabitants stand in the same relation to God as the piano sonata to the pianist. He sustains each of us in being from moment to moment with painstaking care and, at each of those moments, observes and monitors us with an intensity of perception next to which Ireneo Funes with his passion flower is but a pale approximation; anxiously bends over us, so to speak, and holds us in his abyssal gaze—waiting with a heart ablaze with divine love for us to turn to him.
For now it does not matter whether any of this is true; it matters only whether it has relevant entailments for human behaviour among those who believe it is true. And so it does. For it entails that human relations have the profoundest imaginable moral and spiritual importance.
Most of us would approach an ancient artefact of immeasurable value in an attitude of quiet reverence—especially when under the gaze of the museum curator. But on theism every person you meet exists under the burning gaze of God and is of immeasurable value to him; the thrice-holy God who, in the person of Jesus Christ, literally died for love of them. For any rational and sincere Christian, abusing or even insulting another human being (let alone murdering them) should be as unthinkable as entering a church and desecrating a holy relic.
It is also a fundamental principle of Christianity that humans are made imago dei or “in the image of God” inasmuch as we have a God-given capacity for reason, spirituality and moral awareness. To express this sightly differently, something of what God is exists as an essential part of each person—meaning that each person is intimately associated with the most tremendous and holy thing at the heart of Ultimate Reality. In contrast to atheism, which reduces man to a concretion of atoms shaped by mindless natural processes, Christianity affirms and vouchsafes the eternal mystery and sacredness of persons. 
3. Christianity Provides the Strongest Possible Reason and Motive for Treating Others with Self-sacrificial Kindness
To understand this last claim you will first need to note the distinction between an obligatory act and a supererogatory act.
An obligatory act is one which it is wrong not to do. People have an obligation to feed their children, for instance, and under normal circumstances are morally culpable if they do not do it. A supererogatory act, on the other hand, is one which is good but not obligatory. It is good in this way to volunteer at the local soup kitchen but you are not morally culpable if you do not do it.
Importantly, obeying a reasonable command from an authority is an obligation—particularly when significant benefits have been received. A teenage boy, for instance, has an obligation to mow the lawn when his father instructs him to do this because his father is an authority from whom he receives important benefits. Something interesting therefore happens when an authority commands us to perform a supererogatory act: He or she elevates it to an obligation. And when the benefit received is life itself and the command comes from the Ultimate Authority—that obligation is very serious indeed.
The question is whether God has commanded us to perform supererogatory acts for our neighbour. And the answer is yes: In the clearest and strongest possible terms.
When Jesus was asked the Greatest Commandment, he replied that there are two. “You shall love the Lord your God with all your heart and with all your soul and with all your mind” and “You shall love your neighbour as yourself.” It follows from John 14:12 (“Those who accept my commandments and obey them are the ones who love me”) that loving your neighbour is a necessary condition of loving God—the two commands are mutually inclusive. Jesus himself insinuates this when he says the Second Greatest Commandment is “like unto” (i.e. synonymous with) the First; and 1 John 4:20 explicates the point: “If anyone says ‘I love God’ but hates his brother or sister he is a liar.”
And there is no possible doubt that “loving one’s neighbour” here means performing supererogatory acts. To the man with two coats in his closet, Saint Ambrose of Milan said, “One belongs to you and one belongs to the man with no coat”—a gloss on Jesus’ teaching in Luke 3:11. This is a very challenging admonition (it is rightly said of the gospel that it is, “a comfort to the afflicted and an affliction to the comfortable”) but it is also an inescapable requirement of obeying Jesus. If my neighbour is in need and I have the means to help him but prefer to let him suffer to avoid a diminishment of my material goods, then I cannot be said to love him as I love myself. I have failed to obey the Second Greatest Commandment and, ex hypothesi, I have failed to obey the Greatest Commandment also.
Nor can there be any doubt that our neighbour is any fellow human being—for the question was put directly to Jesus in Luke 10:25-29. After teaching the Greatest Commandments, a lawyer asks, “But who is my neighbour?” And in response to this question Jesus narrates a parable in which a Jew is saved from peril by a passing Samaritan.
The Jews and Samaritans of Jesus’ time hated one another—to such a degree that the Jews had destroyed the Samaritan temple on Mount Gerizim and the Samaritans had desecrated the Jewish Temple at Passover. For this reason the message of the parable is clear. “Jesus,” explains Swinburne, “is commanding us to show love to our fellow humans of whatever race or creed, just as the Samaritan showed love to the wounded Jew” —which is perfectly consistent with Jesus’ famous command to “Love your enemies and pray for those who persecute you.”
Christianity, therefore, does not simply forbid a hatred of others by divine command and under pain of eternal loss; nor does it simply recommend treating them with kindness. It imposes a solemn moral obligation to treat others—Muslim, Jew, Hindu or atheist—with self-sacrificial love.
 “You have heard that it was said to those of old, ‘You shall not murder; and whoever murders will be liable to judgment.’ But I say to you that everyone who is angry with his brother will be liable to judgment; whoever insults his brother will be liable to the council; and whoever says, ‘You fool!’ will be liable to the hell of fire.”
 Emerson made the same point more pithily when he wrote: “Sew a thought, reap an action; sew an action, reap a habit; sew a habit, reap a character; sew a character, reap an eternal destiny.”
 See Swinburne’s Providence and the Problem of Evil.
 See The Brain That Changes Itself by Normal Doidge and neuroplasticity and hypofrontality generally.
 I am not denying that atheists can and do abhor violence and value persons. In fact, I claim that there will be no outward difference between a Christian response to the massacre in Christchurch and that of a morally normative atheist—both will be united in shock, heartache and condemnation. What I am suggesting is that the Christian response here will differ in being undergird and intensified by a coherent metaphysical foundation—something “secular humanism” is conspicuously lacking.
 See Swinburne’s Revelation: From Metaphor to Analogy.