الباطن
هو اسمٌ من أسماء الله الحسنى، يدل على صفة (الباطنيَّةِ)؛ أي إنه...
Ibn ‘Abbās (may Allah be pleased with him) reported that the Prophet (may Allah's peace and blessings be upon him) said: "A Muslim's mention of Allah's name is sufficient for him. However, if he forgets to mention Allah's name when he slaughters an animal, he should mention Allah's name [on meat] and then eat it."
شرح الحديث :
This Hadīth indicates that a condition of slaughtering is to mention the name of Allah during the act of slaughtering. Since this is a moment of taking the life of an animal, one should say: "Bismillāh." However, if one forgets to do so, the flesh is lawful to eat, because one did not do that intentionally. Nevertheless, if one does not mention the name of Allah intentionally, the correct ruling is that the flesh is not lawful to eat. In any case, this Hadīth is weak. Authentic proofs indicate that one has to mention the name of Allah when slaughtering so that the animal be lawful for consumption.