It was narrated from Abu Burdah that his father Abu Musa said:
"I came to the Messenger of Allah ﷺ with a group of Asharites and asked him to give us animals to ride. He said: 'By Allah, I cannot give you anything to ride, and I have nothing to give you to ride.' We stayed as long as Allah willed, then some camels were brought to him. He ordered that we be given three she-camels with fine humps. When we left, we said to one another: 'We came to the Messenger of Allah ﷺ to ask him for animals to ride, and he swore by Allah that he would not give us anything to ride, then he gave us something. Let us go back.' So we went to him and we said: 'O Messenger of Allah! We came to you seeking mounts, and you took an oath that you would not give us mounts, then you gave us some mounts.' He said: 'By Allah, I did not give you animals to ride, rather Allah gave you them to ride. I, by Allah, if Allah wills, do not swear and then see something better than it, but I offer expiation for what I swore about, and do that which is better.' Or he said: 'I do that which is better and offer expiation for what I swore about.'"

حَدَّثَنَا أَحْمَدُ بْنُ عَبْدَةَ، أَنْبَأَنَا حَمَّادُ بْنُ زَيْدٍ، حَدَّثَنَا غَيْلاَنُ بْنُ جَرِيرٍ، عَنْ أَبِي بُرْدَةَ، عَنْ أَبِيهِ أَبِي مُوسَى، قَالَ أَتَيْتُ رَسُولَ اللَّهِ ـ ﷺ ـ فِي رَهْطٍ مِنَ الأَشْعَرِيِّينَ نَسْتَحْمِلُهُ فَقَالَ رَسُولُ اللَّهِ ـ ﷺ ـ " وَاللَّهِ مَا أَحْمِلُكُمْ وَمَا عِنْدِي مَا أَحْمِلُكُمْ عَلَيْهِ " . قَالَ فَلَبِثْنَا مَا شَاءَ اللَّهُ ثُمَّ أُتِيَ بِإِبِلٍ فَأَمَرَ لَنَا بِثَلاَثَةِ إِبِلٍ ذَوْدٍ غُرِّ الذُّرَى فَلَمَّا انْطَلَقْنَا قَالَ بَعْضُنَا لِبَعْضٍ أَتَيْنَا رَسُولَ اللَّهِ ـ ﷺ ـ نَسْتَحْمِلُهُ فَحَلَفَ أَلاَّ يَحْمِلَنَا ثُمَّ حَمَلَنَا ارْجِعُوا بِنَا . فَأَتَيْنَاهُ فَقُلْنَا يَا رَسُولَ اللَّهِ إِنَّا أَتَيْنَاكَ نَسْتَحْمِلُكَ فَحَلَفْتَ أَنْ لاَ تَحْمِلَنَا . ثُمَّ حَمَلْتَنَا فَقَالَ " وَاللَّهِ مَا أَنَا حَمَلْتُكُمْ فَإِنَّ اللَّهَ حَمَلَكُمْ وَاللَّهِ مَا أَنَا حَمَلْتُكُمْ بَلِ اللَّهُ حَمَلَكُمْ إِنِّي وَاللَّهِ إِنْ شَاءَ اللَّهُ لاَ أَحْلِفُ عَلَى يَمِينٍ فَأَرَى غَيْرَهَا خَيْرًا مِنْهَا إِلاَّ كَفَّرْتُ عَنْ يَمِينِي وَأَتَيْتُ الَّذِي هُوَ خَيْرٌ " . أَوْ قَالَ " أَتَيْتُ الَّذِي هُوَ خَيْرٌ وَكَفَّرْتُ عَنْ يَمِينِي " .