The article is concerned with selected rules of Islamic penal law. Such a discussion seems necessary (though naturally not sufficient) to attempt to answer the question about the best model of coexistence of sometimes drastically different cultural and normative systems in modern multicultural world. The choice of sharia is justified if we take into account that according to demographic data there are over 38 million of Muslim people living now in Europe. Without a doubt, such a situation may be a challenge because sharia explicitly states that observing laws in the country of residence (kanun) is a duty of every Muslim believer – however provided that the laws do not contradict sharia. There is one striking example of coexistence of different normative systems in Europe. The United Kingdom is the only European country so far which has decided to include Islamic laws in its legal system. Muslim citizens, if they are willing to, can decide property, inheritance, and family disputes in sharia courts and their decisions are recognised by the state. A conscious decision on integration of legal systems should rely on a deeper understanding of the legal system to be integrated into the current one. Understanding sharia requires, first of all, being aware that in the legal culture of Islam there is no division into secular and religious sphere. Hence, the common European perception of sharia as religious law must be considered a mistake. Sharia distinguishes two spheres: ibadat and mu’amalat. Ibadat, that is acts of faith, is the branch of law comprising religious duties of Muslim people. As a rule, breach of ibadat results with punishment in earthly life. Mu’amalat, that is transactions, contains provisions concerning interpersonal relations and protection of five basic human needs: life, religion, family life, property, feelings, and intellect. Yet, it cannot be said that ibadat is religious while mu’amalat is secular law. Together they form sharia and, what is more, they both contain penal provisions. In sharia, penal law is not a separate branch of law and both rules of penal law and sentence administration appear in both branches of sharia. Crime in Islamic law is always a detriment to the society as it infringes social order, God’s order, is a sacrilege (as it is a human infringement of divine rules), and a source of corruption for others. Classification of crimes in sharia is also entirely different from the western one. The basic criterion is the grounds for punishment and crimes are classified as punishable as hudud, kisas (or dijja), and ta’zir. Distinction between deeds punishable under Qur’an (hudud and kisas) and deeds punishable under customary law (ta’zir) is specific for Islamic law. While considering issues related to Islamic penal law, one cannot stop at the literal interpretation of sources of law.