Christians like to link their god with love — indeed, they will go so far as to insist that their god is love, making the link as absolute as possible. It's one thing to claim that a god is loving or even that it is love, but quite another to have good reasons for doing so. The question which non-believers must ask, then, is whether the Christian claims about their god have any merit — indeed, whether the Christians themselves are able to make any sort of case that is reasonable or rational.
Love Without Physical, Material Biology
It's difficult to "test" for love in the same way that we might test for cancer or other physiological changes, despite the fact that love ultimately is a question of physiology and biology. Difficult doesn't mean impossible, though. We can reliably use brain scans to determine which parts of the brain are most active and, therefore, whether self-reports of feelings of love are likely accurate or false. Of course, this presumes that we have a brain to scan; in the case of a deity, no such physical structures exist.
This raises the question of whether it makes any sense to talk about "love" absent a brain, hormones, and other physical structures upon which our love is founded. It is arguable that without these organs and structures, love as we know it cannot exist — perhaps something might plausibly exist, but it call it "love" would be a misuse of the term. It's a convenient misuse, though, because the concept of "love" is so pleasing and makes this deity seem so attractive.
Love Is What You Do... Or Don't Do
For the sake of argument, though, we can set aside the question of whether love can exist absent a brain, mind, and other physical structures and look instead directly at whether the concept is compatible with what we observe. Actions are the best indicator of what a person really believes, thinks, and values — and this may be especially true when it comes to something like love.
We can't "see" the emotion we call love, but we can see whether claims that one "loves" are reflected in their behavior. Indeed, it's normal for us to place more weight on actions than on mere words when it comes to whether a person really does "love" another (or their country, or something else). Perhaps the most popular phrase in the Christian theological lexicon is "for God so loved the world...," but if God has loved the world, then how has that love been expressed?
Christian "Love"
Everywhere we turn we can find suffering, violence, and brutality that any moderately-concerned human being wouldn't hesitate to help. If you really loved someone, would you let them starve to death? Would you let them be tortured to death? Would you allow them to be born into a live in which a fatal disease would quickly bring it to an end? If you loved a child, would you allow your neighbor to kidnap, torture, rape, and murder that child?
None of this makes sense — love may be compatible with a certain degree of allowing individuals to explore their own path in life and perhaps fail, but there are limits. Conservative Christians certainly recognize and accept that such limits exist because they insist that their "love" for others is compatible with using the state to prevent them from behavior that they think will condemn them to hell.
Unfortunately for humanity and other life on this planet, those limits are surpassed on a daily basis. If there is some deity, even the Christian one, and if it is capable of experiencing something like what we call emotions, then whatever feeling it has with respect to humanity it cannot be called "love." Even if it's the closest this deity can come to what we call love, it's far to distant from any sort of love to warrant being placed in the same category.
We have an obligation to accuracy in our words and concepts. It's a violation of both intellectual and ethical standards to use words which mean one thing and then apply them to situations where nothing analogous can be found — that simply confuses the issue and makes understanding more difficult.
Christians might argue that their god's love was adequately expressed by sending his son to be punished in our place for all our transgressions. Punishing an innocent person for the crimes of others is hardly an example of love, though — it's neither an expression of love to the person being punished nor to the ones who should be.
At best it might be described as an expression of mercy towards those who should be punished, but this is more than outweighed by the expression of violent indifference towards the innocent who is forced to suffer. This situation is made all the worse by the fact that there are apparently no outside requirements or standards being imposed on the Christian god and forcing it to make this exchange — it's a choice, and a terribly immoral one at that.
For God Was So Indifferent to Humanity, That it Did Nothing
If the Christian god exists, it's arguable that the single best label for its attitude towards humanity is indeed "indifference," if not "pitiless indifference." Even hatred causes a being to act and is predicated on caring what happens to the object of hatred. No less than love, hatred for someone means that you care about them on some level.
Indifference, however, means really not caring what happens — not caring if one lives or dies, prospers or fails, experiences pleasure or suffering. We are justified in adding the adjective "pitiless" because of the apparent lack of mercy or pity in reaction to our suffering.
In the end, there's no discernible difference between an indifferent god and an indifferent universe without any gods. What we experience is exactly what we would expect to if there were no gods, or at least no gods that care. It makes more sense to not multiply entities unnecessarily, so there's no good reason to assume the existence of unnecessary, indifferent gods — there's just the universe and it doesn't care. Only we care and that's why we're able to recognize such a dramatic difference between how we respond to events around us and how the universe responds.
