The Impurity Status of Blood: Explanation and Classification According to Scholars
Maintaining the purity of one's body, clothing, and place during prayer is an obligation emphasized in the Qur'an, such as in Surah Al-Muddatstsir verse 4. A common question is whether blood is an impurity that can invalidate prayer. Based on the consensus of major scholars from the four schools of thought (Shafi'i, Maliki, Hanbali, Hanafi), blood is fundamentally ruled as impure, in accordance with the word of Allah SWT in Surah Al-An'am verse 145 which forbids the consumption of flowing blood (masfuh).
Scholars classify blood to determine its impurity status. The flowing blood of animals (dam masfuh), the blood of pigs, dogs, and carrion is absolutely impure, except for the remnants on meat that has been washed and cooked. The blood of small insects like mosquitoes is considered pure. Regarding human blood, the majority of scholars consider flowing blood to be impure, though there are other opinions stating it is pure. All scholars agree that the blood of martyrs (syuhada) is pure. Menstrual blood and postpartum bleeding are absolutely impure, with specific guidance provided for purifying garments that become soiled.
In practice, there is the concept of ma'fuw (forgiven) for blood impurities that are difficult to avoid. According to Sheikh Bin Baz, a small amount of impure blood (approximately the size of a fingernail) is forgiven. Blood from a wound, boil, or skin disease is also forgiven, provided that: its discharge is unintentional, it does not overflow from the wound area, and it has not mixed with another fluid or substance. If these conditions are met, the prayer is not invalidated.
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