Religion and medicine have always been close bed partners throughout history. Not only do religious systems offer some explanation for suffering in general and for sickness in particular, but illness presents a challenge to all concerned and it is not surprising that appeal is frequently made to supernatural entities for help, whether this be to provide an explanation to cope with the specific sickness or to offer cure, or something which we might term a ‘miracle’. Religious systems seem to have little internal logical self-consistency. Episodes of sickness of any degree of intensity frequently occasion the question ‘why me?’ and raise concerns relating to theodicy, that is, attempts to reconcile the existence of evil or suffering in the world with the belief in an omniscient, omnipotent and benevolent God; in effect, the problem of evil. Consequently all religions offer a range of solutions to this problem, ranging from ideas that evil originates from mankind to the idea that suffering has educational value or the conclusion that we can never know God's ways, as exemplified in the book of Job, to list just a few.

The term ‘healing’ within religion is generally more holistic than that within biomedicine and encompasses body, psyche and soul. The monotheistic religions deploy a plethora of techniques related to healing, both individual and collective; ranging from prayer, ritual, the recitation of myths and religious texts to the more empirical techniques of laying on of hands and the syncretic techniques deployed by religious healers in many parts of the world which combine prayer with the use of medicines.