Can boar bristle paintbrushes transfer najasah to painted walls and people?

A pig is considered to be essentially filthy (najas al-ayn), hence the position of the Hanafi School and that of many other imams, is that the skin, hair, and all other components of the pig remains filthy even after the tanning process is carried out.

Imam Ibn Abidin (Allah have mercy on him) explains:

?(al-Haskafi’s statement: ?Pigskin cannot be purified?) this is due to the fact that a pig is considered essentially filthy (najas al-ayn), in that the essence of a pig with all its body-components is filthy, whether dead or alive. Hence, the filthiness is not because of the blood that is contained in its body like other non-pure animals. Therefore, it does not accept purification (by tanning or other such methods)?.? (Radd al-Muhtar, 1/204)

Imam al-Haskafi (Allah have mercy on him) states specifically with regards to pig-hair:

?The hair of a dead animal other than a pig??.is pure?

Imam Ibn Abidin (Allah have mercy on him) explains:

?According to Imam Abu Yusuf, which is the Dhahir al-Riwaya (established narration) in the Hanafi School, the hair of a pig is considered filthy and impure. This is the position chosen by Imam al-Kasani in his al-Bada?i and Imam al-Mawsili in his al-Ikhtiyar. Thus, if one prayed with pig-hair more than the amount of a dirham, one’s prayer would not be valid?? (Radd al-Muhtar ala al-Durr al-Mukhtar, 1/206)

In light of the above, it will not be permitted to acquire and use a hair brush that is made of boar bristles. If one is relatively certain of the hair brush being predominantly made of pig-hair, then one must avoid using the brush. If one offers salat with pig-hair (or any other part of a pig’s body) attached to one’s self or clothing, then one would have to repeat one’s prayer.

However, using dry hair brushes would not make one’s hair filthy, for the coming into contact with dry pig-hair does not transfer the filth to one’s body. Thus, the prayers you performed after using a dry hair brush made of boar bristles would not have to be repeated. However, if one’s hair or body comes into contact with a wet boar bristles brush, then one should wash one’s hair and repeat the prayer. (See: Fatawa Mahmudiyya, 17/393-3940)

And Allah knows best

(Mufti) Muhammad ibn Adam
Darul Iftaa
Leicester , UK