There have been many attempts among theologians and philosophers to answer this question. However, it seems that there is not an answer that works to everybody’s satisfaction. But I think the biggest difficulty is talking about this issue directly, given that many doctrinal propositions are highly nuanced or qualified to the point where they can be construed to say many different things. The only way to know what a person is really trying to convey is to look at the prevailing theme that their teaching revolves around. That centric theme guides their treatment of the more subtle details.
For example, many Christians acknowledge the sovereignty of God and believe that there are events in our lives that happen by God’s design. Furthermore, many Christians will acknowledge that there are bad events in our lives that ultimately lead to a positive outcome, and that God in His mysterious ways was involved with that process. However, many Christians also want to avoid the concept of fatalism, which is the idea that everything in our lives was preplanned to happen regardless of what we do or don’t do. Many Christians have a desire to emphasize the role that human will, or the devil, or forces of nature, or faith of believers play in our own lives or world affairs, to encourage personal responsibility and avoid making God responsible for evil.
I think that 90% of Christians would express the ideas in the above paragraph. And there is a Biblical basis for those all those ideas: the sovereignty of God / predestination (Eph. 1:11), human will / decision making capacity and consequences (Deut. 30:19), adversities in life caused by the devil (1 Peter 5:8-9), Christians’ authority over forces of evil (Eph. 6:12).
But when we take those basic ideas, and put them together to explain why a particular event just happened, that is where things get argumentative. When Christians try to explain the cause of an event, the impression that their statement conveys depends not on the statement itself but rather on the overall focus of their theology. For example, some Christians, despite acknowledging both the sovereignty of God and human will, really want for people to focus on free will. For these people, the center of their theology is personal responsibility and accountability for choices. Their biggest fear is that people will abandon personal responsibility, or that God would be seen as the cause of a disaster. Avoiding such ideas is the cornerstone of their theology, even though they will acknowledge the predestination of some events if pressed about it. Thus, if you ask these people why something happened, they will give an answer that conveys an idea of free will, the devil’s activity, or Christians’ spiritual authority first and foremost, even if they hint of predestination in the fine print.
Other Christians are primarily worried about people taking too much credit for their own accomplishments. They think that a focus on predestination is essential to living in reliance on God; otherwise, people will become self-righteous about making the right choices. They are also worried about the implications for the character and wisdom of God if He created a world that He could not control, knowing everything that would take place. However, these people will acknowledge that part of life is making decisions and that there are powers of evil; however, these concepts are clearly put under the umbrella of predestination. If you ask these people why something bad happened, they want you to come away with the idea that things are not out of God’s control in the ultimate sense, even if they acknowledge intermediary forces at play.
Where do I stand on all of this? Well, I think that if you read my other writings on the blog, you could make a guess about my stance that better reflects my views than any direct statement I could make. I do not think it yields much benefit to argue with people over the causes of evil. The reason is that a person’s stance is rooted in other matters of theology, and you would have to uproot much of your opponent’s theology to convince him or her of your stance. People will sound very decisive and confident when they talk about predestination or free will. But I think they are acting confident largely because their answer is backed by an accumulation of other doctrinal elements and personal experiences (I say this about myself as well).
So, don’t let people intimidate you by hard and fast statements. Know that there is a much more complicated story behind what they are saying.