Sunan Ibn Majah, Chapter: The Chapters of Establishing the Prayer and the Sunnah Regarding Them

"When the Messenger of Allah (saw) said the Takbir (Allah Akbar), he would remain silent between the Takbir and the recitation. I said: 'May my father and mother be ransomed for you! I noticed that you are silent between the Takbir and the recitation; please tell me what you say then.' He said: 'I say: 'Allahumma ba'id baini wa baina khatayaya kama ba'adta bainal-mashriqi wal-maghrib; Allahumma naqqini min khatayaya kath-thawbil abyad minad-danas; Allahummaghsilni min khatayaya bil-ma'i waththalji wal-barad. (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 purified of dirt; O Allah, cleanse me of my sins with water and snow and hail)."