Is the nullifying touch restricted to the hand, and what are the implications of touching non-skin body parts?
Chapter on What Nullifies Purification
Al-Mughni
Book of Purification
Primary text
The nullifying touch is not restricted to the hand; rather, any part of the body touching any part of the woman's skin with desire invalidates ablution, whether it is an original or an extra limb. This view is supported by the generality of the legal text, as limiting it without proof is arbitrary. Touching a woman's hair, nail, or tooth does not invalidate ablution, nor does her touching with her hair, tooth, or nail, because these are not grounds for divorce or Zihar (a form of divorce). Hair is not considered impure upon an animal's death or when cut while alive.
Supporting text
A narration from al-Awza'i suggests that touching only invalidates ablution if done by one of the limbs of Wudu. The view that touch does not nullify if it is through a barrier is held by the majority of scholars. Malik and al-Laith, however, maintain that it invalidates if the garment is thin, as desire is present. The argument against this is that the body itself was not touched, which is analogous to touching clothes, and desire alone without contact is insufficient.