Is God's promise to perform a supererogatory act with the intention of compelling oneself to it considered a vow (nadhr)? And does a vow uttered after a period of silence and saying "Insha'Allah (God willing)" take effect? What is the ruling on a vow made under the duress of obsessive-compulsive disorder (waswas)? And what is the ruling on a vow when in doubt about having said "Insha'Allah" after it?

A promise is not a vow (nadhr), and it is recommended to fulfill it, especially between a servant and their Lord. The exception in a vow, an oath (yamin), and dhihar (a pre-Islamic form of divorce) is valid, provided it is immediately connected to them without any intervening extraneous speech or a prolonged silence. A vow made under the influence of obsessive whisperings (waswasah) is not binding if the waswasah has removed free choice; otherwise, it is binding. Doubting an exception is treated like not having made an exception at all, and the default is its absence. It is advised to disregard obsessive whisperings and seek Allah's help.