Should Du`a'-ul-Istiftah (opening supplication when starting the Prayer) be recited after Takbirat-ul-Ihram (saying: "Allahu Akbar [Allah is the Greatest]" upon starting Prayer) and before the recitation of Surah Al-Fatihah?
It is Sunnah (action following the teachings of the Prophet) to recite Du`a'-ul-Istiftah after Takbirat-ul-Ihram and before starting to recite Surah Al-Fatihah. It is authentically reported on the authority of
Abu Hurayrah (may Allah be pleased with him) who said:
The Messenger of Allah (peace be upon him) used to observe silence for a short while between the Takbir (saying Allahu Akbar at commencing the Prayer) and the recitation of the Qur'an. I asked him, 'May my father and mother be sacrificed for you, O Messenger of Allah. What do you say during your period of silence between the Takbir and the recitation?' He (peace be upon him) said, 'I say (these words): O Allah, remove my sins from me as You have removed the east from the west. O Allah, purify me from sins as a white garment is purified from filth. O Allah, wash away my sins with water, snow, (Part No. 6; Page No. 375) and hail.'
You may refer to other formulas of Du`a'-ul-Istiftah that have been reported in the books of Sunnah (whatever is reported from the Prophet), like the book entitled Al-Kalim Al-Tayyib by
Ibn Taymiyyah and the book of Al-Adhkar by Al-Nawawi.May Allah grant us success. May peace and blessings be upon our Prophet Muhammad, his family, and Companions.