The Prophet ﷺ said: If anyone takes a vow but does not name it, its atonement is the same as that for an oath, if anyone takes a vow to do an act of disobedience, its atonement is the same as that for an oath, if anyone takes a vow he is unable to fulfill, its atonement is the same as that for an oath, but if anyone takes a vow he is able to fulfill, he must do so. Abu Dawud said: This tradition has been transmitted by Waki' and others on the authority of 'Abd Allah b. Sa'id b. Abi al-Hind, but they traced it no farther back than Ibn 'Abbas.  

أَنَّ رَسُولَ اللَّهِ ﷺ قَالَ مَنْ نَذَرَ نَذْرًا لَمْ يُسَمِّهِ فَكَفَّارَتُهُ كَفَّارَةُ يَمِينٍ وَمَنْ نَذَرَ نَذْرًا فِي مَعْصِيَةٍ فَكَفَّارَتُهُ كَفَّارَةُ يَمِينٍ وَمَنْ نَذَرَ نَذْرًا لاَ يُطِيقُهُ فَكَفَّارَتُهُ كَفَّارَةُ يَمِينٍ وَمَنْ نَذَرَ نَذْرًا أَطَاقَهُ فَلْيَفِ بِهِ  

[Machine] "Narrated by the Messenger of Allah ﷺ, 'Whoever makes a vow but does not specify it, then its expiation is like the expiation of an oath. And whoever makes a vow in disobedience to Allah, then its expiation is like the expiation of an oath. And whoever makes a vow that they cannot afford, then its expiation is the expiation of an oath. And whoever makes a vow that they can afford, then let them fulfill it.'"  

عَنْ رَسُولِ اللهِ ﷺ قَالَ «مَنْ نَذَرَ نَذْرًا لَمْ يُسَمِّهِ فَكَفَّارَتُهُ كَفَّارَةُ يَمِينٍ وَمَنْ نَذَرَ نَذْرًا فِي مَعْصِيَةِ اللهِ فَكَفَّارَتُهُ كَفَّارَةُ يَمِينٍ وَمَنْ نَذَرَ نَذْرًا لَا يُطِيقُهُ فَكَفَّارَتُهُ كَفَّارَةُ يَمِينٍ وَمَنْ نَذَرَ نَذْرًا يُطِيقُهُ فَلْيَفِ»  

"مَنْ نَذَرَ نَذْرًا (وَ) (*) لَمْ يُسَمِّهِ فَكَفارَتُهُ كفَّارَةُ يَمينٍ، وَمَنْ نَذَرَ (نَذْرًا) (* *) فِي مَعْصِيةٍ فَكَفَّارتُه كفَّارَةُ يَمِينٍ، وَمَنْ نَذَرَ نَذْرًا لا يُطِيقهُ فَكَفَّارتُه كفَّارَةُ يَمِينٍ".  

"مَنْ نَذَرَ نَذْرًا وَلَمْ يُطِقْه فَكَفَّارَتُه كَفَّارَةُ يَمِينٍ وَمَنْ نَذَرَ نَذْرًا أَطَاقَهُ فَليَفِ بِهِ".