Atonement for a broken oath is:
1 – Feeding ten poor people, for each poor person half a saa’ (a weight measure) of the country’s foodstuff.
2- Providing ten poor people with clothes that cover their private parts and enable them to perform Salah while wearing them.
3 – Setting a bondsperson free
If one finds none of these three, he should move to fasting; he should fast for three consecutive days, according to the majority of Fuqaha’ (jurists).
(Allah will not call you to account for your thoughtless oaths, but He will hold you accountable for deliberate oaths. The penalty for a broken oath is to feed ten poor people from what you normally feed your own family, or to clothe them, or to free a bondsperson. But if none of this is affordable, then you must fast three days. This is the penalty for breaking your oaths. So be mindful of your oaths. This is how Allah makes things clear to you, so perhaps you will be grateful.) (Al-Ma’idah 5: 89)
كفارة اليمين لها ثلاث خصال
إطعام عشرة مساكين لكل مسكين نصف صاع من قوت البلد
كسوة عشرة مساكين (أي لباس) و هو ما يكفي لستر العورة و أداء الصلاة.
تحرير رقبة
فإن لم يجد أحد هذه الثلاث انتقل إلى الصيام فيصوم ثلاثة أيام متتابعات في قول جمهور الفقهاء.
(لَا يُؤَاخِذُكُمُ اللَّهُ بِاللَّغْوِ فِي أَيْمَانِكُمْ وَلَٰكِن يُؤَاخِذُكُم بِمَا عَقَّدتُّمُ الْأَيْمَانَ ۖ فَكَفَّارَتُهُ إِطْعَامُ عَشَرَةِ مَسَاكِينَ مِنْ أَوْسَطِ مَا تُطْعِمُونَ أَهْلِيكُمْ أَوْ كِسْوَتُهُمْ أَوْ تَحْرِيرُ رَقَبَةٍ ۖ فَمَن لَّمْ يَجِدْ فَصِيَامُ ثَلَاثَةِ أَيَّامٍ ۚ ذَٰلِكَ كَفَّارَةُ أَيْمَانِكُمْ إِذَا حَلَفْتُمْ ۚ وَاحْفَظُوا أَيْمَانَكُمْ ۚ كَذَٰلِكَ يُبَيِّنُ اللَّهُ لَكُمْ آيَاتِهِ لَعَلَّكُمْ تَشْكُرُونَ
المائدة 5: 89