Abu Bakr As-Siddiq had never broken his oaths till Allah revealed the expiation for the oaths. Then he said, "If I take an oath to do something and later on I find something else better than the first one, then I do what is better and make expiation for my oath."  

أَنَّ أَبَا بَكْرٍ ؓ لَمْ يَكُنْ يَحْنَثُ فِي يَمِينٍ قَطُّ حَتَّى أَنْزَلَ اللَّهُ كَفَّارَةَ الْيَمِينِ وَقَالَ لاَ أَحْلِفُ عَلَى يَمِينٍ فَرَأَيْتُ غَيْرَهَا خَيْرًا مِنْهَا إِلاَّ أَتَيْتُ الَّذِي هُوَ خَيْرٌ وَكَفَّرْتُ عَنْ يَمِينِي  

The Prophet ﷺ said, "O ʿAbdur-Rahman bin Samura! Do not seek to be a ruler, because if you are given authority for it, then you will be held responsible for it, but if you are given it without asking for it, then you will be helped in it (by Allah): and whenever you take an oath to do something and later you find that something else is better than the first, then do the better one and make expiation for your oath."  

قَالَ النَّبِيُّ ﷺ يَا عَبْدَ الرَّحْمَنِ بْنَ سَمُرَةَ لاَ تَسْأَلِ الإِمَارَةَ فَإِنَّكَ إِنْ أُوتِيتَهَا عَنْ مَسْأَلَةٍ وُكِلْتَ إِلَيْهَا وَإِنْ أُوتِيتَهَا مِنْ غَيْرِ مَسْأَلَةٍ أُعِنْتَ عَلَيْهَا وَإِذَا حَلَفْتَ عَلَى يَمِينٍ فَرَأَيْتَ غَيْرَهَا خَيْرًا مِنْهَا فَكَفِّرْ عَنْ يَمِينِكَ وَأْتِ الَّذِي هُوَ خَيْرٌ  

I went to the Prophet ﷺ along with a group of Al-Ashʿariyin in order to request him to provide us with mounts. He said, "By Allah, I will not provide you with mounts and I haven't got anything to mount you on." Then we stayed there as long as Allah wished us to stay, and then three very nice looking she-camels were brought to him and he made us ride them. When we left, we, or some of us, said, "By Allah, we will not be blessed, as we came to the Prophet ﷺ asking him for mounts, and he swore that he would not give us any mounts but then he did give us. So let us go back to the Prophet ﷺ and remind him (of his oath)." When we returned to him (and reminded him of the fact), he said, "I did not give you mounts, but it is Allah Who gave you. By Allah, Allah willing, if I ever take an oath to do something and then I find something else than the first, I will make expiation for my oath and do the thing which is better (or do something which is better and give the expiation for my oath).  

أَتَيْتُ النَّبِيَّ ﷺ فِي رَهْطٍ مِنَ الأَشْعَرِيِّينَ أَسْتَحْمِلُهُ فَقَالَ وَاللَّهِ لاَ أَحْمِلُكُمْ وَمَا عِنْدِي مَا أَحْمِلُكُمْ عَلَيْهِ قَالَ ثُمَّ لَبِثْنَا مَا شَاءَ اللَّهُ أَنْ نَلْبَثَ ثُمَّ أُتِيَ بِثَلاَثِ ذَوْدٍ غُرِّ الذُّرَى فَحَمَلَنَا عَلَيْهَا فَلَمَّا انْطَلَقْنَا قُلْنَا أَوْ قَالَ بَعْضُنَا وَاللَّهِ لاَ يُبَارَكُ لَنَا أَتَيْنَا النَّبِيَّ ﷺ نَسْتَحْمِلُهُ فَحَلَفَ أَنْ لاَ يَحْمِلَنَا ثُمَّ حَمَلَنَا فَارْجِعُوا بِنَا إِلَى النَّبِيِّ ﷺ فَنُذَكِّرُهُ فَأَتَيْنَاهُ فَقَالَ مَا أَنَا حَمَلْتُكُمْ بَلِ اللَّهُ حَمَلَكُمْ وَإِنِّي وَاللَّهِ إِنْ شَاءَ اللَّهُ لاَ أَحْلِفُ عَلَى يَمِينٍ فَأَرَى غَيْرَهَا خَيْرًا مِنْهَا إِلاَّ كَفَّرْتُ عَنْ يَمِينِي وَأَتَيْتُ الَّذِي هُوَ خَيْرٌ أَوْ أَتَيْتُ الَّذِي هُوَ خَيْرٌ وَكَفَّرْتُ عَنْ يَمِينِي  

The Prophet ﷺ said, "We (Muslims) are the last in the world, but will be foremost on the Day of Resurrection."  

عَنِ النَّبِيِّ ﷺ قَالَ نَحْنُ الآخِرُونَ السَّابِقُونَ يَوْمَ الْقِيَامَةِ  

"By Allah, if anyone of you insists on fulfilling an oath by which he may harm his family, he commits a greater sin in Allah's sight than that of dissolving his oath and making expiation for it."  

رَسُولُ اللَّهِ ﷺ وَاللَّهِ لأَنْ يَلِجَّ أَحَدُكُمْ بِيَمِينِهِ فِي أَهْلِهِ آثَمُ لَهُ عِنْدَ اللَّهِ مِنْ أَنْ يُعْطِيَ كَفَّارَتَهُ الَّتِي افْتَرَضَ اللَّهُ عَلَيْهِ  

Messenger of Allah ﷺ said, "Anyone who takes an oath through which his family may be harmed, and insists on keeping it, he surely commits a sin greater (than that of dissolving his oath). He should rather compensate for that oath by making expiation."  

قَالَ رَسُولُ اللَّهِ ﷺ مَنِ اسْتَلَجَّ فِي أَهْلِهِ بِيَمِينٍ فَهْوَ أَعْظَمُ إِثْمًا لِيَبَرَّ يَعْنِي الْكَفَّارَةَ