Is the slaughter performed by a Muslim or a People of the Book permissible if they omit or forget the invocation (Tasmiyah)?
General Chapter
Al-Mughni
Book of Hunting and Slaughter
Primary text
The slaughter performed by any capable Muslim or People of the Book—man or woman, adult or child, free or slave—is permissible, and there is no known disagreement on this. Consensus among scholars prohibits slaughtering by one who lacks intellect, such as a child, madman, or intoxicated person incapable of comprehension, as intent is required for validity, akin to acts of worship. If the slaughterer is a People of the Book and intentionally omits the invocation or mentions other than Allah's name, the animal is unlawful. This is based on the injunctions: 'And do not eat of that upon which the name of Allah has not been mentioned' (Quran 6:121) and concerning that dedicated to other than Allah (Quran 5:3).
Supporting text
If it is unknown whether the slaughterer made the invocation or not, the slaughtered animal is permissible because Allah has permitted the slaughter of Muslims and People of the Book, acknowledging that one cannot ascertain the actions of every individual slaughterer. 'A'isha reported that when people newly converted from polytheism brought meat without knowing if they had mentioned Allah's name, the Prophet commanded, 'Say the name yourselves and eat.'