be fair in dealings

وَلَا تَقْرَبُوا۟ مَالَ ٱلْيَتِيمِ إِلَّا بِٱلَّتِى هِىَ أَحْسَنُ حَتَّىٰ يَبْلُغَ أَشُدَّهُۥ ۖ وَأَوْفُوا۟ ٱلْكَيْلَ وَٱلْمِيزَانَ بِٱلْقِسْطِ ۖ لَا نُكَلِّفُ نَفْسًا إِلَّا وُسْعَهَا ۖ وَإِذَا قُلْتُمْ فَٱعْدِلُوا۟ وَلَوْ كَانَ ذَا قُرْبَىٰ ۖ وَبِعَهْدِ ٱللَّهِ أَوْفُوا۟ ۚ ذَٰلِكُمْ وَصَّىٰكُم بِهِۦ لَعَلَّكُمْ تَذَكَّرُونَ

Stay well away from the property of orphans, except with the best [intentions], until they come of age; give full measure and weight, according to justice’- We do not burden any soul with more than it can bear- ‘ when you speak, be just, even if it concerns a relative; keep any promises you make in God’s name. This is what He commands you to do, so that you may take heed’-

وَأَوْفُوا۟ ٱلْكَيْلَ إِذَا كِلْتُمْ وَزِنُوا۟ بِٱلْقِسْطَاسِ ٱلْمُسْتَقِيمِ ۚ ذَٰلِكَ خَيْرٌ وَأَحْسَنُ تَأْوِيلًا

Give full measure when you measure, and weigh with accurate scales: that is better and fairer in the end.