1. What we generally mean by evil appears to be both individual and systemic or structural. Individual persons can think evil thoughts and do evil deeds. All structures or systems in cultures, whether economic, political, cultural, religious, military or otherwise, seem to have some form of evil built into them (racism, classism, agism, sexism, etc.).
2. Spiritual traditions vary as to how they handle the causes of evil. However, in the myths and stories and scriptures of many of them there is often an emphasis on Chaos vs. Order. Often some kind of mythical battle between Chaos and Order. Chaos and Evil are often linked. Chaos can lead to destruction, death, despair, meaninglessness. Order can lead to construction, life, hope, meaning. But Chaos can also lead to creativity, and Chaos becomes an energizing force. Order can also lead to a kind of status quo, maintaining of what is, a deterrent to progress and its own kind of evil. So in many spiritual traditions the goal is a balance between Chaos and Order, in which each energizes the other. Sometimes a Satan figure or a Dark God is pictured in opposition to a good God who maintains order, but this opposition is often pictured as both a balancing and an opposition.
3. If we are looking at evil in individuals we could say that we have a Shadow side to our self (from Carl Jung). All of us have a dark side, recognized by our egotism, selfishness, anti-social desires, antipathy to certain persons, desires for revenge or harm, etc. Though some act on these desires, most of us do not. A sign of healing is to admit the Shadow within us, call it what it is, think of it as an integral part of who we really are, balance our chaos and order, recognize the good and evil within us, and experience how this recognition can lead to wholeness, empathy, inclusivity, compassion, and balance. A sign of illness is to deny the Shadow, deny the evil in us, act as if all of the dark side is or can be overcome by salvation or ethical behavior or submission to a god or a cause.
4. The primary evil in systemic or structural evil appears to be Oppression. Oppression of ethnic minorities, women, the poor, the disabled, the powerless, and so on. Individuals in power positions in society oppress and persons within the structures - all of us, in fact - participate in the oppression, whether willingly or not. Oppressive structures are a given in society, much as we abhor them.
5. How does Spirit deal with Evil? I believe that Spirit is compassionate, life-affirming and energizing. Spirit energizes us to recognize evil, in us, in systems, to call oppression by its name, and to work to mitigate its power. I believe that Spirit energizes us to balance Chaos and Order in our lives in order to release our creative powers. I do not believe that Spirit or any God or gods will "intervene" or "fix it," will right wrongs, overcome evil with good, get rid of the "bad guys." Spirit works in, among, with all of us for compassion, creativity, and liberation. Liberation from oppression is a life-long, never-ending process. But we rejoice in the realization that we are co-workers with Spirit.