Christians believe in a God who is perfect in power, knowledge, and goodness. Yet, it does not take a lot of examination to be confronted with the reality that our world is permeated with all kinds of evil. Whether we turn on the news, walk out our front door, or take an honest look into our own hearts, the presence of evil is an ever-present reality. The apparently conflicting beliefs in a perfectly loving God and the existence of evil have given rise to what philosophers call the problem of evil and suffering. If God were truly mighty, then He would have the knowledge of our suffering and the desire and ability to end it; and yet, evil remains.  
No Way to Deny Evil
The problem of evil is often presented as a problem for Christians, but it’s important to note that it’s a reality everyone has to confront. All worldviews have their own attempts to make sense of suffering and provide a solution. Whether one believes in God or not, there appears to be something genuinely wrong with the world. Many worldviews, however, simply try and solve the problem by denying that evil exists. 
While there are many nuances to atheism, it’s usually tied to a view called materialism. Under this view the sum-total of all reality is explained by everything we can see and touch around us. There are no spiritual realities, no gods, no soul, and certainly nothing like angels and demons. While this view might sound sensible to a modern scientific mindset, it is not often appreciated that it also means that other immaterial realities such as logic, personhood, love, and good and evil would not exist as well. These things are not open to physical investigation; they cannot be observed through a telescope or examined under a microscope. 
Heading east, many aspects of Buddhist and new-age thought also see pain and suffering as illusory. Buddhism focuses on the idea that we have radically misunderstood that we even exist. The doctrine of anatman argues that the self is merely a momentary mistaken existence that will achieve Nirvana once it becomes enlightened of this fact. By continuing to believe that we have existence, we allow for the illusion that we are experiencing pain and suffering.  Much of new age thought swings in the other direction and says that we are God, but just have a case of mistaken identity. Once we awaken to our divine potential we can escape the erroneous belief that we are suffering. 
The Christian, on the other hand, doesn’t have to take the path of denying that genuine evil exists in the world. In fact, evil can point us to God. 
No Way to Deny God
When we speak of evil we presuppose that this universe isn’t how it ought to be. But once we bring “ought” into the conversation we have to appeal to a standard by which we can measure exactly how things ought or ought not be. A cartographer, for example, ought to draw his relief map according to the topography of the land. A musician ought to play certain notes if she wants to play a particular song. Ethics, like a map, is judged according to an external reference point. The nature of all-perfect God, then, serves as the standard by which we can speak meaningfully about right and wrong.     
Further, the idea that Christians are created in the image of God means that we have objective worth and dignity that ought not be violated. If the atheist is correct, then ultimate reality is explained by physics and chemistry. The atheist Carl Sagan was famous for remarking that we are merely a cosmic accident made of star stuff, but surely when a child is lost the parents do not grieve over merely losing an accidental piece of “stuff.” Rather, as beings created in the image of an infinitely valuable God, we are more valuable than all the stuff in the entire universe. 
This explains part of why suffering exists in the world. We are relational creatures because we are made in the image of a God whose very essence is relational (a Trinity). If meaningful relationships are to be possible, then we must have not only the ability to love each other, but to hurt each other as well. A genuine relationship would not be possible if every time we tried to slander another person, God made praises roll off our tongue instead. No one would desire a relationship where they knew a scowl actually lay behind the coerced smile of their friend. 
No Other Way
But the Christian God does not merely give a standard by which we can speak meaningfully about good and evil. God is not simply a philosophical reference point or conclusion of an argument. God desires that we believe in Him and not merely believe that He is. Suffering awakens us to the reality that we need God in our brokenness. If God always protected us from the realities of sin, then we would never realize that we are guilty and helpless before a mighty God and in great need of mercy, forgiveness, and rescue. 
Suffering is a hard truth of living in a fallen world, but like Peter we can say, “Lord, to whom shall we go? You have the words of eternal life” (John 6:68). If you give up Jesus, you haven’t solved the problem of evil, you have only turned away from its solution. A crucified Messiah defied the expectations of the Jews, but through the unexpected our rescue became possible. The earthly foolishness of the cross became the strength of a mighty God (1 Corinthians 18-25). As such, in the midst of suffering Christians can take comfort in knowing that evil has already lost the battle even if it has not yet been eliminated.
Indeed, the apostle Paul was stoned and left to die, often found himself imprisoned, whipped and beaten with rods on multiple occasions, shipwrecked three times, and ultimately executed; but he almost absurdly remarks that his life is a “light momentary affliction.” This is because he knows that suffering is “preparing for us an eternal weight of glory beyond all comprehension” (2 Corinthians 4:17). In times of suffering, then, we can reflect upon the cross of Christ as it has demonstrated that God found it worthwhile to suffer alongside us. His incomprehensible suffering was not pointless. Even though we do not have access to the reason behind particular evils in the world we can know that our suffering is not meaningless. We can have confidence that this life is as bad as it will ever get, for we stand within the foyer of eternity, being prepared for the good that is ahead.   

1 Speaking in generalities is helpful in categorizing belief systems, but we should be careful assuming what people believe. Not all atheists, for example, hold to materialism and not all Buddhism would affirm that our existence is ultimately mistaken. A good evangelist will listen more than they speak. We can only make a bridge to the Gospel when we have understood the person we are trying to share it with. 

2 Society and culture are often used as an attempt to ground ethics; however, two main problems arise. First, if each society becomes the ultimate standard for what is right, then it becomes impossible to critique another culture. North Korea, for example, could not be condemned as they are living according to their own ethical standard. Second, society can no longer be spoken of as getting better or worse as what is right is always defined by the current status quo. As such, all attempts to reform society would necessarily be immoral. Thus, the standard of morality must transcend society. What else can that be but God?