19. Shares of Inheritance (Kitab Al-Fara'id) - كتاب الفرائض
1) Chapter: What Has Been Related About Teaching The Knowledge Of Inheritance
Narrated Abdullah ibn Amr ibn al-'As:
The Prophet (ﷺ) said: Knowledge has three categories; anything else is extra; a precise verse, or an established sunnah (practice), or a firm obligatory duty.