What is the boundary of the hand for which the full Diyah is due upon severance?
Chapter on Diyat (Blood Money) for Wounds
Al-Mughni
Book of Blood-Money (Diyyāt)
Primary text
The hand for which the full Diyah is due upon severance extends from the wrist (al-Kow'a). This is deduced from the general usage of the term 'hand' when unrestricted, as evidenced by the ruling for theft, where amputation occurs from the wrist for the verse concerning thieves (Quran 5:38), and similarly, ablution (Tayammum) requires wiping the hands up to the wrists.
Supporting text
If the hand is cut above the wrist, such as from the elbow or mid-forearm, the ruling held by Ahmad in the narration of Abu Talib, and supported by 'Ata, Qatadah, al-Nakha'i, Ibn Abi Layla, and Malik, is that only the Diyah of the hand is due. However, the apparent position in the Shafi'i school suggests that in addition to the hand's Diyah, a discretionary indemnity (Hukm) is due for the excess portion severed above the wrist because the essential function of the hand—grasping, taking, and pushing with the palm—is associated with the part up to the wrist, and the remainder is subordinate. Therefore, an additional discretionary payment is due for the excess, just as it would be if the hand were severed immediately after the wrist.