Ideally both the logical theodicy defense and the evidential theodicy defense should leave us prepared to have a good groundwork to deal with the existential problem of evil. I call our experience of evil the “existential” problem of evil because we must face it in our own way, and the greatness of the evil varies from person to person. While the previous two categories of evil allow us to step back and view the problem without any attachment, the existential problem of evil focuses on our everyday lives and experiences with evil. How we evaluate that evil is purely subjective, which poses a problem for explaining why the evil is allowed. To the three-year-old, not being able to have ice cream for evil one can face; for the adult it’s losing one’s job, losing a spouse, losing a child, or so on.
What is consistent about the existential problem of evil is that it seems all the academic efforts in theodicy fall apart in a personal crisis. One of the more famous examples is C.S. Lewis, who dealt with the problem of evil in his book The Problem of Pain. Yet, when he suffered an incredible loss in his own life (the death of his wife through cancer), he openly questioned God and found no solace in his theodicy, all of which is painfully evidence in his Grief Observed. When faced with the existential problem of evil it seems there is simply no reasoned response to it, which some would argue is a problem for Christians.
However, I would contend that the lack of a reasoned response is not a problem, but expected within a Christian worldview (though not necessarily a theistic worldview). As stated earlier, evil is the privation of good and good is an attribute of God. We must remember that His attributes cannnot be separated (for God is not composed of parts, but is simple). That means if evil is the absence of good, then it will in turn also be the absence of all other attributes of God. There won’t be any good in evil, but there also won’t be any wisdom, eternality, logic, and so on. Since evil is the absence of the power of God’s goodness, it follows that evil is also devoid of God’s reason as well. Therefore, all evil is by definition senseless and irrational, so when we experience evil there isn’t a reasoned response to it.
While we can offer a reasoned response to evil when we’re simply an observer, because we can draw back and look at it within the scheme of things, when we’re experiencing the evil we lack this ability because we’re in the midst of an irrational action. In fact, the greater the evil, the more illogical and senseless it is. The more we suffer or watch someone close to us suffer, the less likely we are to find an answer because evil is not only the privation of good, but the privation of reason as well (and all of God’s attributes). Since evil is devoid of the power of God (His goodness, His reason, and so on), we shouldn’t try to make sense of what is by nature senseless.
Some might take issue with me saying that evil is the privation of God. Perhaps it is better to flesh this out before moving on. When I say that evil is the privation of God as a whole, which includes all His attributes, what I mean is that it’s the privation of God’s power, for God Himself cannot be removed from anything (this would entail that He has limits). Therefore, evil is the privation of God’s power, but even then this comes in degrees.
A less evil (or sin) will entail a minor privation of God’s power, though not His presence. A greater evil would entail a major privation of God’s power, though not His presence. Due to the existence of free will, God’s power (as it is experienced) can be withheld without His presence being withheld (for God can remain hidden if He so chooses).
Some might contend that my argument falls apart when we consider the communicable and uncommunicable attributes of God. For instance, God is love and humans can love, God is rational and we can reason, etc. Here I would argue that while we can love, we cannot do so perfectly, thus we don’t technically share in the attribute of God itself, but rather in the power of God’s attribute. For humans can increase or decrease in love because we are accessing the power of God, but God cannot increase or decrease in love because it is a part of who He is (and His power is ever present in Himself).
Sadly, I don’t have space to go through a full defense of this – which could possibly require an entire other section and if I ever write a book on this issue, I might dedicate substantial space to this issue – but will leave my defense here. Since God cannot be divided and evil is a privation of the power of His goodness, it should follow that it is a privation of all of God’s power to some degree. This would include reasoning (as well as love, which is why an act of love can never be evil).
Certainly, though, there must be some explanation to the existential problem of evil. There must be something we can turn to, something we can grasp a hold of. I would argue that there is, but it only makes sense if we work out the problems with the logical problem of evil and evidential problem of evil first. When those are settled, we are then supplied with the necessary framework to explain the existential problem of evil. I believe this is best accomplished through a Unified Theodicy.
 I would assert that this explanation of evil as a privation of God’s whole power (to varying degrees, depending on the evil) is almost essential to my Unified Theodicy. Without the belief that evil is a privation of God’s power, a Unified Theodicy would collapse.