(18) باب مَنْ حَلَفَ فَاسْتَثْنَى
It was narrated from Ibn 'Umar that the Prophet said:
"Whoever swears an oath and says: 'If Allah wills', then if he wishes he may go ahead, and if he wishes he may not, without having broken his oath."
Reference: Sunan an-Nasa'i 3793
In-book reference: Book 35, Hadith 33
English translation: Vol. 4, Book 35, Hadith 3824