Does a small amount of impure outflow (like vomit or blood) from a non-outlet invalidate ablution?
Chapter on What Nullifies Purification
Al-Mughni
Book of Purification
Primary text
Ablution is only invalidated by a large amount of such outflow, not a small amount. This is supported by the actions and statements of several Companions. Ibn 'Abbas stated that if blood is excessive ('fahish), re-performance of prayer is required. Ibn Abi Awfa prayed after spitting blood. Ibn 'Umar squeezed a blister, blood emerged, and he prayed without performing ablution. Several Companions spoke on this matter, and the narrated traditions regarding minimal outflow support this, such as the narration transmitted by Ad-Daraqutni from the Prophet (PBUH): "Ablution is not required from a drop or two." The position held by Abu Hanifah is that if blood flows, ablution is required, but if it stops at the top of the wound, it is not required, based on the general meaning of the hadith: "Whoever vomits or bleeds during his prayer, let him perform ablution."
Supporting text
Some associates of our school hold a differing narration that even a small amount invalidates ablution, though this narration is not recognized. Al-Qadi stated that only one narration suggests non-invalidation. The prevailing opinion among the Companions is that minimal outflow does not invalidate it. The hadith used by the opposition regarding minimal outflow is considered weak in authenticity, as it was not mentioned by compilers of the Sunan who consequently acted against it.