The Islamic penal system relies directly upon divinely inspired texts encompassed in the Shari'a (the collection of legal provisions divinely revealed to the Prophet). Because the legal system is essentially a divine revelation, conformity to and application of Islamic penal decisions are inseparable from faith in God. Further, the criminal law provides for both earthly punishment and punishment in the hereafter. There is no dichotomy in the Islamic legal system between criminal law and moral principles. The cornerstone of contemporary Islamic criminal law is the legality principle, which provides that there is no crime or punishment unless established by law. This means that law is not retroactive, i.e., behavior cannot be punished unless there was a law prohibiting it at the time of its commission. The evenhanded application of the criminal law is an ancient principle in Islam, such that the law does not discriminate according to the economic, political, or social status of the offender or victim. Principles of criminal procedure rest in the right to commence criminal action and the extent to which this right can be guaranteed to the victim in certain crimes. Another principle deals with the duty of a criminal judge to ensure the competence and credibility of evidence submitted in a criminal case to ensure that punishments are justly imposed. The presumption of the innocence of the accused underlies the latter principle. Forty-nine footnotes are provided.