(2) باب الْحَلِفِ بِمُصَرِّفِ الْقُلُوبِ
It was narrated from Salim that his father said:
"The oath by which the Messenger of Allah used to swear was: 'No, by the Controller of the hearts.'" (FR)
Reference (FR): Sunan an-Nasa'i 3762 (FR)
In-book reference (FR): Book 35, Hadith 2 (FR)
English translation (FR): Vol. 4, Book 35, Hadith 3793 (FR)