Sahih al-Bukhari 6693
Sahih al-Bukhari · Book 83: Oaths and Vows · To fulfil one's vow
Narrated `Abdullah bin `Umar:
حَدَّثَنَا خَلاَّدُ بْنُ يَحْيَى ، حَدَّثَنَا سُفْيَانُ ، عَنْ مَنْصُورٍ ، أَخْبَرَنَا عَبْدُ اللَّهِ بْنُ مُرَّةَ ، عَنْ عَبْدِ اللَّهِ بْنِ عُمَرَ ، نَهَى النَّبِيُّ صلى الله عليه وسلم عَنِ النَّذْرِ وَقَالَ " إِنَّهُ لاَ يَرُدُّ شَيْئًا، وَلَكِنَّهُ يُسْتَخْرَجُ بِهِ مِنَ الْبَخِيلِ " .
The Prophet (ﷺ) forbade the making of vows and said, "It (a vow) does not prevent anything (that has to take place), but the property of a miser is spent (taken out) with it."