Sunan an-Nasa'i 3830
سنن النسائي#3830Sahihأَخْبَرَنَا أَحْمَدُ بْنُ سُلَيْمَانَ، قَالَ حَدَّثَنَا عَفَّانُ، قَالَ حَدَّثَنَا وُهَيْبٌ، قَالَ حَدَّثَنَا أَيُّوبُ، عَنْ نَافِعٍ، عَنِ ابْنِ عُمَرَ، عَنِ النَّبِيِّ صلى الله عليه وسلم قَالَ " مَنْ حَلَفَ عَلَى يَمِينٍ فَقَالَ إِنْ شَاءَ اللَّهُ فَهُوَ بِالْخِيَارِ إِنْ شَاءَ أَمْضَى وَإِنْ شَاءَ تَرَكَ " .
It was narrated from Ibn 'Umar that the Messenger of Allah said:"Whoever swears an oath and says, 'If Allah wills,' then he has the choice: If he wishes, he may go ahead, and if he wishes he may not
Scholarly Authentication
The label above is the grade most of these scholars gave — one dissenting opinion no longer speaks for all of them. If any scholar calls a narration fabricated, that verdict is shown instead, whatever the others say. Each scholar's own wording:
In-book reference: 35:70