The Prophet ﷺ said, "If somebody on the demand of a judge takes an oath to grab (a Muslim's) property and he is liar in it, he will meet Allah Who will be angry with him". So Allah revealed,:-- 'Verily! those who purchase a small gain at the cost of Allah's Covenant and their oaths..' (3.77) 'Al- Ashath came while ʿAbdullah was narrating (this) to the people. Al-Ashath said, "This verse was revealed regarding me and another man with whom I had a quarrel about a well. The Prophet ﷺ said (to me), "Do you have any evidence?' I replied, 'No.' He said, 'Let your opponent take an oath.' I said: I am sure he would take a (false) oath." Thereupon it was revealed: 'Verily! those who purchase a small gain at the cost of Allah's Covenant....' (3.77) (See Hadith No. 72, Vol 6).  

النَّبِيُّ ﷺ لاَ يَحْلِفُ عَلَى يَمِينِ صَبْرٍ يَقْتَطِعُ مَالاً وَهْوَ فِيهَا فَاجِرٌ إِلاَّ لَقِيَ اللَّهَ وَهْوَ عَلَيْهِ غَضْبَانُ فَأَنْزَلَ اللَّهُ {إِنَّ الَّذِينَ يَشْتَرُونَ بِعَهْدِ اللَّهِ} الآيَةَ فَجَاءَ الأَشْعَثُ وَعَبْدُ اللَّهِ يُحَدِّثُهُمْ فَقَالَ فِيَّ نَزَلَتْ وَفِي رَجُلٍ خَاصَمْتُهُ فِي بِئْرٍ فَقَالَ النَّبِيُّ ﷺ أَلَكَ بَيِّنَةٌ قُلْتُ لاَ قَالَ فَلْيَحْلِفْ قُلْتُ إِذًا يَحْلِفُ فَنَزَلَتْ {إِنَّ الَّذِينَ يَشْتَرُونَ بِعَهْدِ اللَّهِ} الآيَةَ