Sahih al-Bukhari 6628
Book 83: Oaths and Vows · Narrated by Ibn `Umar
Arabic
حَدَّثَنَا مُحَمَّدُ بْنُ يُوسُفَ، عَنْ سُفْيَانَ، عَنْ مُوسَى بْنِ عُقْبَةَ، عَنْ سَالِمٍ، عَنِ ابْنِ عُمَرَ، قَالَ كَانَتْ يَمِينُ النَّبِيِّ صلى الله عليه وسلم " لاَ وَمُقَلِّبِ الْقُلُوبِ ".
English translation
Narrated Ibn `Umar:The oath of the Prophet (ﷺ) used to be: "No, by Him who turns the hearts
Reference: Sahih al-Bukhari 6628, Book of Oaths and Vows. English translation by Dr. Muhammad Muhsin Khan.