Sayyiduna Abu Huraira (may Allah be pleased with him) narrated: When the Prophet (peace and blessings be upon him) would say the opening takbeer in prayer, he would remain silent for a short while before beginning the recitation. I asked, "O Messenger of Allah! May my parents be sacrificed for you! What is the silence you observe between the opening takbeer and the recitation?" The Prophet (peace and blessings be upon him) replied: "I say: O Allah! Distance me from my sins as You have distanced the East from the West. O Allah! Purify me of my sins as a white garment is cleansed of dirt. O Allah! Wash away my sins with water, snow, and hail."
Hadith Referenceمسند اسحاق بن راهويه / كتاب الصلوٰة / 142
Hadith Takhrij«بخاري ، كتاب الاذان ، باب مايقول بعد التكبير ، رقم : 744 . مسلم ، كتاب المساجد ، باب ما يقال بين تكبيرة الاحرام القراءة ، رقم : 598 . سنن ابوداود ، رقم : 781 . سنن نسائي ، رقم : 60 .»
Sayyiduna Abu Hurairah (may Allah be pleased with him) narrated, the Messenger of Allah (peace and blessings be upon him) would remain silent for a brief moment when saying Allahu Akbar (the takbir). The narrator said, I asked Sufyan: At the time of the opening takbir of the prayer? He replied: Yes.
Hadith Referenceمسند اسحاق بن راهويه / كتاب الصلوٰة / 143