Apostasy, that in technical term means blasphemy after accepting Islam or giving up it, in Islamic jurisprudence, causes punishment and some important legal effects such as breach of marriage and division of properties between hairs at-law. meanwhile the freedom of opinion in Islam is generally important and reputable. Therefore, some of religious scholars, in removing all the doubt that there is incompatibility between apostasy commandments and freedom of opinion in Islam, have argued on the axis of explaining the philosophy of apostate punishment by showing importance and it’s bad conclusions and others, on the axis of apostasy proofs, have tried to reveal it’s conditions and hence to adjust and purify the mentioned doubt. It is thought that the certainty signification of apostasy proofs is the man who is considered dangerous for Islam because of his actions after giving up of it in spite of society’s illustration