(7) باب قضاء الحاجة
and Al-Hakim reported that:
"Urination is the main cause of punishment in the grave". [Its chain of narrators is authentic]. (ID)
Reference (ID): Bulugh al-Maram 104 (ID)
In-book reference (ID): Book 1, Hadith 123 (ID)
English translation (ID): Book 1, Hadith 110 (ID)