The church tells you god does not act arbitrarily. god always acts, or allows acts to happen in order to teach the living certain lessons. They tell you that many times god acts as he does in order to save a person from some future evil or trial. They also tell you god acts as he does in order to bring your attention to the fact that you are committing some terrible sin, or you are not doing something that he wants you to do. In other words, god causes or allows bad things to happen to innocent people (them) in order to gain the attention of the guilty (you). This makes about as much sense as a father whipping the good child in order to make the bad child correct his mischievous ways. Such an explanation simply cannot be accepted by thinking people.