(39) باب الاِسْتِثْنَاءِ .
It was narrated that Ibn 'Umar said:
"The Messenger of Allah said: 'Whoever swears an oath and says: If Allah wills, then he has made an exception.'" (ES)
Reference (ES): Sunan an-Nasa'i 3829 (ES)
In-book reference (ES): Book 35, Hadith 69 (ES)
English translation (ES): Vol. 4, Book 35, Hadith 3860 (ES)