This article deals with the moral-legal aspects of crime. According to the intention of the legislator every crime is a sin, however not every sin is a crime. The Author attempts to distinguish between these two realities. According to the canonical criminal law sin does not produce legal effects. It covers only the spiritual sphere of man. A crime, on the other hand, according to can. 1321 § 1 CIC/83, is an external violation of a law or order, which has a penal sanction. This sanction is either expressly indicated by a juridical norm or imposed by ecclesiastical authority. The objective and subjective elements of the crime are discussed. The occurrence of a crime and the moral sanctity of the perpetrator who has committed a criminal act should be made dependent on each other. The Author, concluding his considerations, states after the legislator that the criminal responsibility is subjected to an unlawful external act, gravely culpable, committed with intentional as well as unintentional guilt, which is the source of the criminal investigatio.