Sunan an-Nasa'i, Volume 5, Book 44, Hadith 4585 (DarusSalam) ⓘ

It was narrated that Abu Salih heard Abu Saeed Al-Khudri say: "I said to Ibn Abbas: 'Do you think that what you are saying is something that you found in the Book of Allah, or something that you heard from the Messenger of Allah?' He said: 'I did not find it in the Book of Allah, nor did I hear it from the messenger of Allah, rather Usamah bin Zaid told me that the Messenger of Allah said: 'Riba is only in credit."'

أَخْبَرَنَا قُتَيْبَةُ بْنُ سَعِيدٍ، قَالَ حَدَّثَنَا سُفْيَانُ، عَنْ عَمْرٍو، عَنْ أَبِي صَالِحٍ، سَمِعَ أَبَا سَعِيدٍ الْخُدْرِيَّ، يَقُولُ قُلْتُ لاِبْنِ عَبَّاسٍ أَرَأَيْتَ هَذَا الَّذِي تَقُولُ أَشَيْئًا وَجَدْتَهُ فِي كِتَابِ اللَّهِ عَزَّ وَجَلَّ أَوْ شَيْئًا سَمِعْتَهُ مِنْ رَسُولِ اللَّهِ صلى الله عليه وسلم قَالَ مَا وَجَدْتُهُ فِي كِتَابِ اللَّهِ عَزَّ وَجَلَّ وَلاَ سَمِعْتُهُ مِنْ رَسُولِ اللَّهِ صلى الله عليه وسلم وَلَكِنْ أُسَامَةُ بْنُ زَيْدٍ أَخْبَرَنِي أَنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم قَالَ ‏ "‏ إِنَّمَا الرِّبَا فِي النَّسِيئَةِ ‏" ‏ ‏.‏