[Machine] The Ansar used to give less than the required amount of dates in their zakat. Then Allah revealed the verse:

"O you who have believed, spend from the good things which you have earned and from that which We have produced for you from the earth. And do not aim toward the defective therefrom, spending [from that] while you would not take it [yourself] except with closed eyes. And know that Allah is Free of need and Praiseworthy." (Quran 2:267)

The word "defective" in this verse refers to the inferior dates. If someone owes you something and they give you something less, they have reduced your right. But if you accept it, then it is considered as closing your eyes to it.  

كَانَتِ الْأَنْصَارُ يُعْطُونَ فِي الزَّكَاةِ الشَّيْءَ الدُّونَ مِنَ التَّمْرِ فَنَزَلَتْ {يَا أَيُّهَا الَّذِينَ آمَنُوا أَنْفِقُوا مِنْ طَيِّبَاتِ مَا كَسَبْتُمْ وَمِمَّا أَخْرَجْنَا لَكُمْ مِنَ الْأَرْضِ وَلَا تَيَمَّمُوا الْخَبِيثَ مِنْهُ تُنْفِقُونَ وَلَسْتُمْ بِآخِذِيهِ إِلَّا أَنْ تُغْمِضُوا فِيهِ} [البقرة 267] قَالَ فَالدُّونُ هُوَ الْخَبِيثُ وَلَوْ كَانَ لَكَ عَلَى إِنْسَانٍ شَيْءٌ فَأَعْطَاكَ شَيْئًا دُونَ فَقَدْ نَقَصَكَ بَعْضَ حَقِّكَ فَإِذَا قَبِلْتَهُ فَهُوَ الْإِغْمَاضُ