According to search-discovered classical Islamic jurisprudence, the concept of Killing (القتل - al-Qatl) is governed by the foundational principle of the sanctity of human life (ḥurmat al-nafs), as emphatically stated in the Quran (5:32). Classical commentators like Ibn Kathir and Al-Tabari explain that this verse establishes the unlawful taking of a single innocent life as tantamount to the murder of all humanity. Islamic law (Shariah), as detailed by jurists such as Al-Qurtubi, therefore strictly prohibits murder (Qatl al-ʿAmd) as a major sin with severe spiritual consequences (Quran 4:93). However, the Quran establishes a framework of justice, not vengeance, permitting the taking of life only under strictly regulated legal processes. This includes the law of just retribution (Qisas) for murder (Quran 2:178), which is the right of the victim's family and administered by the state, and specific rules for killing in legitimate, defensive warfare (Qital). Furthermore, Islamic law distinguishes accidental killing (Qatl al-Khata'), for which the penalty is compensation (Diyah) and expiation, not retribution (Quran 4:92). This comprehensive synthesis across numerous verses and scholarly traditions establishes a legal and ethical system where life is protected by default, and its taking is only permissible within a framework of divine law and justice.