What is the ruling on bequests? And when are they obligatory?

Question:
What is the correct view regarding the obligatory bequest, and which scholars held the view of the obligatory bequest?

Answer:
The obligatory bequest is among the rights that are upon him; it is obligatory for him to bequeath the debts for which there is no clear evidence, such as expiations and rights owed to people. He is required to bequeath them.
The right that is upon him for Allah or for His servants, he should bequeath it. As for bequeathing one-third, in obedience to Allah, or one-quarter, or one-fifth, this is recommended.