What is the minimum amount of prayer one must complete to fulfill the obligation (wujub)?
Chapter on Prayer Times
Al-Mughni
Book of Prayer
Primary text
The amount of the prayer incumbent upon the worshipper is equivalent to the Takbirat al-Ihram (the opening declaration of consecration). This is supported by the general principle that the minimum threshold for obligation corresponds to the essential commencement of the act.
Supporting text
Al-Shafi'i holds that the minimum amount is one full Rak'ah (unit of prayer), based on narrations from 'Abd al-Rahman and Ibn 'Abbas. He draws an analogy that since reaching one Rak'ah permits the continuation of prayer, it should be the minimum threshold, similar to reaching one Rak'ah in Jumu'ah (Friday prayer). Imam Malik mandates a minimum of five Rak'ahs.