Hadith 501640
Chapter 3: Prayer - كتاب الصلاة
وَحَدَّثَنِي عَنْ مَالِكٍ، عَنِ ابْنِ شِهَابٍ، عَنْ عَلِيِّ بْنِ حُسَيْنِ بْنِ عَلِيِّ بْنِ أَبِي طَالِبٍ، أَنَّهُ قَالَ كَانَ رَسُولُ اللَّهِ صلى الله عليه وسلم يُكَبِّرُ فِي الصَّلاَةِ كُلَّمَا خَفَضَ وَرَفَعَ فَلَمْ تَزَلْ تِلْكَ صَلاَتَهُ حَتَّى لَقِيَ اللَّهَ .
Yahya related to me from Malik from Ibn Shihab that AIi ibn Husayn ibn Ali ibn Abi Talib said, "The Messenger of Allah, may Allah bless him and grant him peace, used to say, 'Allah is greater' whenever he lowered himself and raised himself, and he continued to pray like that until he met Al lah ."
Reference Muwatta Malik 501640
USC-MSA web (English) reference : Book 3, Hadith 18