"I heard him meaning Ibn 'Abbas allowing exchange (of Dirhams for Dirham etc., if extra was given) and that was narrated from him. Then I heard that he has taken back this opinion. I met him in Makkah and said: 'I heard that you had taken back (your opinion).' He said: 'Yes. That was just my own opinion, but Abu Sa'eed narrated from the Messenger of Allah ﷺ that he forbade exchange (of like items if extra is given)."'
عَنْ ذَلِكَ فَلَقِيتُهُ بِمَكَّةَ فَقُلْتُ إِنَّهُ بَلَغَنِي أَنَّكَ رَجَعْتَ قَالَ نَعَمْ إِنَّمَا كَانَ ذَلِكَ رَأْيًا مِنِّي وَهَذَا أَبُو سَعِيدٍ يُحَدِّثُ عَنْ رَسُولِ اللَّهِ ﷺ أَنَّهُ نَهَى عَنِ الصَّرْفِ