Imamiyyah and Sunni jurists consider the religious punishment for adultery with incest as murder. However, there is a serious difference of opinion regarding the scope of the ruling. Some consider this ruling to be limited to relative incest, while others, due to the use of the word “incest” in the relevant narrations, consider foster incest to be included in this punishment. However, the Islamic Penal Code 92 is in accordance with the first view in Article 224 and has considered the aforementioned punishment to be limited to relative incest. This research, which was conducted using a descriptive-analytical method and by examining jurisprudential, narrative and legal sources, shows that the view of assigning the aforementioned ruling to relative incest is controversial. The most important arguments presented include the criticism of the well-known arguments in Imamiyyah jurisprudence (appearance, tabader, the rule of da’) and the unification of the criteria for relative and foster incest in Sunni jurisprudence. Therefore, it is proposed to amend Article 224 of the Islamic Penal Code 92 by adding the clause “incestuous incest”.