Is adding extra supplications or remembrances (Dhikr) during bowing (Ruku') or prostration (Sujud) permissible?
Chapter on the Description of Prayer
Al-Mughni
Book of Prayer
Primary text
Adding supplications and remembrances found in established narrations during Ruku' and Sujud is legislated. Aisha reported that the Prophet, peace be upon him, frequently said in his Ruku' and Sujud: 'Subhanaka Allahumma wa bihamdik, Allahumma ighfirli' (Glory be to You, O Allah, and praise be to You; O Allah, forgive me), interpreting the Quran. Abu Sa'id reported that the Prophet, peace be upon him, instructed Mu'adh: 'When you place your face in prostration, say: O Allah, help me to thank You and worship You well.' Ali stated that the most beloved speech to Allah while in prostration is: 'My Lord, I have wronged myself, so forgive me.' Abu Hurairah reported that the Prophet, peace be upon him, used to say in his Sujud: 'O Allah, forgive all my sins, the small and the great, the first and the last, the secret and the apparent.' The command to increase supplication during prostration indicates that it is highly likely to be answered.
Supporting text
The view of Al-Qadi is that exceeding 'Subhana Rabbiyal A'la' (Glory be to my Lord, the Most High) is not recommended in the obligatory prayer. There are two narrations regarding voluntary prayers. This is based on the fact that only the command for Tasbih (glorification) was narrated from the Prophet, peace be upon him, and the Sunnah of the Prophet must be followed above all else. However, the command for glorification does not negate the permissibility of other supplications, just as the command for Tashahhud does not negate the legislation of making Du'a (supplication).