If there was a God testing us we should have been able to eat grass like most other mammals, but instead humans kill and eat those animals.
I would not want to use this issue as an argument for or against a divine being.
However, I would point out that nature is full of animals eating other animals, and in some ways, it might be considered a good thing, as it can reduce animal suffering. This is because the predatory animals often target the weak or lame animals in the pack for their prey. If those weaker animals are weak because of ill heath or advancing age, they may be suffering. So then killing these weak animals reduces the level of suffering in the animal world. It means the pack is always filled with health and vitality, because the predators eke out the weak and the ill.
Unfortunately in the human sphere, we invented civilisation, medical science and hospitals to take care of the weak and frail, and there are thus no longer any natural forces of nature that will prune weak humans. This may actually increase human suffering.
In my case, I have a chronic physical disease which debilitates and weakens me, and causes a lot suffering. If I lived in the natural world, I would have be killed by the predatory forces of nature long ago, which would have been the end to my suffering. But I am kept alive by my civilisation, and so go on suffering.
I am always amazed at the youthful vitality of the more primitive and religious countries: where conditions are harsh because they don't have advanced civilisation, you find populations are young and healthy, as people don't live long. But in advanced civilisations, there is a lot more old age, along with the chronic diseases that come with age.
I think that argument of Epicurus would be more pertinent to use here if the word "evil" in that text were replaced with the word "suffering".
For humans beings, especially those on this forum, who are probably here because of horrible levels of suffering, it is the fact that in this cosmos, terrible suffering can be inflicted on the minds of conscious beings. Why is this so? Why is there suffering, such as horrendous mental health conditions, or terrible physical pain from chronic disease? This suffering does not necessarily arise from evil; it may just arise by accident or misfortune, such in those who have a chronic physical or mental illness.
It is only because we are conscious that suffering can occur. If we were just smart but unconscious computers, there could be no suffering, as suffering requires self awareness, which unconscious machines do not have.
It is said that our conscious life is a gift; but for some it can become a curse, when a generally content mental disposition is replaced by a state of terrible suffering.
This is the philosophical issue I have grappled with since developing some nasty chronic mental health symptoms, which were triggered by catching a virus which infected my brain. The virus affected my physical brain, and this then led to anguishing mental states of psychiatric ill health.
Conscious minds exist within our universe, but why can there be such intense suffering in this conscious mental landscape?
Consciousness is something we currently have little understanding of. Consciousness is studied in many disciplines, including philosophy, psychology, religion, mysticism, biology, biochemistry, and more recently in physics (with some postulating that consciousness may be a quantum phenomenon in the brain). Some believe consciousness merely arises when the complexity of the computing hardware (our brain in the human case) reaches a certain point; others believe that consciousness may be a fundamental (and even transcendental) force in the universe which our physical brain just taps into.
We know how to eliminate consciousness from the brain (anaesthetics will remove consciousness without affecting how the rest of the brain functions); but we don't have the ability to eliminate suffering from the conscious brain.
