بُلُوغُ الْمَرَامِ
Bulugh al-Maram 120
The Book of Purification
Taking Ghusl (bath) And the precepts regarding Sexual Impurity
وَلَهُمَا فِي حَدِيثِ مَيْمُونَةَ: { ثُمَّ أَفْرَغَ عَلَى فَرْجِهِ, فَغَسَلَهُ بِشِمَالِهِ, ثُمَّ ضَرَبَ بِهَا اَلْأَرْضَ }
Narrated Maimuma (rad): Allah’s Messenger (ﷺ) poured water over his private parts and washed them with his left hand. He then struck his hand against the earth.
Bulugh al-Maram, 120