عَنْ سَعِيدِ بْنِ الْمُسَيَّبِ رَضِيَ اللَّهُ عَنْهُ قَالَ قَالَ عُمَرُ رَضِيَ اللَّهُ عَنْهُ إِنَّ آخِرَ مَا نَزَلَ مِنَ الْقُرْآنِ آيَةُ الرِّبَا وَإِنَّ رَسُولَ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَآلِهِ وَسَلَّمَ قُبِضَ وَلَمْ يُفَسِّرْهَا فَدَعُوا الرِّبَا وَالرِّيبَةَ
It is narrated from Saeed bin Musayyib, he says: Sayyiduna Umar (may Allah be pleased with him) said: The last verse of the Noble Qur'an to be revealed is the one concerning usury, but it happened that the Noble Prophet (peace and blessings be upon him) passed away and he had not yet explained its interpretation, so leave usury as well as anything in which there is doubt of usury.