In this article I discuss the concept of evil. I begin by showing that the concept of evil is not religiously neutral. Here, I will discuss the Western view of evil, influenced by Judaism and Christianity. Subsequently, I discuss Leibniz’s classic distinction between three forms of evil - metaphysical, physical and moral - and introduce the categories of natural and non-moral evil. Next, I show that one and the same event may be good in one respect and evil in another. Thus, the passion of Christ is a physical evil when we look at the suffering undergone, a moral evil when we look at the act of those who inflict it on Him, and a moral good when we look at the act of Christ: He gives His life for His friends. This I call the ambiguity of evil. Finally, I discuss two views on the origin of evil: dualism and the view of evil as a privation of a good that should be there, and argue in favour of the second.