Do not sell gold for gold, except like for like, and don't increase something of it upon something; and don't sell silver unless like for like, and don't increase some thing of it upon something, and do not sell for ready money something to be given later.  

أَنَّ رَسُولَ اللَّهِ ﷺ قَالَ لاَ تَبِيعُوا الذَّهَبَ بِالذَّهَبِ إِلاَّ مِثْلاً بِمِثْلٍ وَلاَ تُشِفُّوا بَعْضَهَا عَلَى بَعْضٍ وَلاَ تَبِيعُوا الْوَرِقَ بِالْوَرِقِ إِلاَّ مِثْلاً بِمِثْلٍ وَلاَ تُشِفُّوا بَعْضَهَا عَلَى بَعْضٍ وَلاَ تَبِيعُوا مِنْهَا غَائِبًا بِنَاجِزٍ  

'Abdullah (b. 'Umar) went and I along with the person belonging to Banu Laith entered (the house) of Sa'id al-Khudri, and he ('Abdullah b. Umar) said: I have been informed that you say that Messenger of Allah ﷺ forbade the sale of silver with silver except in case of like for like, and sale of gold for gold except in case of like for like. Abu Sa'id pointed towards this eyes and his ears with his fingers and said: My eyes saw, and my ears listened to Messenger of Allah ﷺ saying: Do not sell gold for gold, and do not sell silver for silver except in case of like for like, and do not increase something of it upon something, and do not sell for ready money something, not present, but hand to hand.  

لَهُ رَجُلٌ مِنْ بَنِي لَيْثٍ إِنَّ أَبَا سَعِيدٍ الْخُدْرِيَّ يَأْثُرُ هَذَا عَنْ رَسُولِ اللَّهِ ﷺ فِي رِوَايَةِ قُتَيْبَةَ فَذَهَبَ عَبْدُ اللَّهِ وَنَافِعٌ مَعَهُ وَفِي حَدِيثِ ابْنِ رُمْحٍ قَالَ نَافِعٌ فَذَهَبَ عَبْدُ اللَّهِ وَأَنَا مَعَهُ وَاللَّيْثِيُّ حَتَّى دَخَلَ عَلَى أَبِي سَعِيدٍ الْخُدْرِيِّ فَقَالَ إِنَّ هَذَا أَخْبَرَنِي أَنَّكَ تُخْبِرُ أَنَّ رَسُولَ اللَّهِ ﷺ نَهَى عَنْ بَيْعِ الْوَرِقِ بِالْوَرِقِ إِلاَّ مِثْلاً بِمِثْلٍ وَعَنْ بَيْعِ الذَّهَبِ بِالذَّهَبِ إِلاَّ مِثْلاً بِمِثْلٍ فَأَشَارَ أَبُو سَعِيدٍ بِإِصْبَعَيْهِ إِلَى عَيْنَيْهِ وَأُذُنَيْهِ فَقَالَ أَبْصَرَتْ عَيْنَاىَ وَسَمِعَتْ أُذُنَاىَ رَسُولَ اللَّهِ ﷺ يَقُولُ لاَ تَبِيعُوا الذَّهَبَ بِالذَّهَبِ وَلاَ تَبِيعُوا الْوَرِقَ بِالْوَرِقِ إِلاَّ مِثْلاً بِمِثْلٍ وَلاَ تُشِفُّوا بَعْضَهُ عَلَى بَعْضٍ وَلاَ تَبِيعُوا شَيْئًا غَائِبًا مِنْهُ بِنَاجِزٍ إِلاَّ يَدًا بِيَدٍ  

This hadith has been narrated on the authority of Abu Sa'id al-Khudri through another chain of transmitters.  

عَنِ النَّبِيِّ ﷺ  

Do not sell gold for gold and silver for silver weight for weight or of the same quality.  

أَنَّ رَسُولَ اللَّهِ ﷺ قَالَ لاَ تَبِيعُوا الذَّهَبَ بِالذَّهَبِ وَلاَ الْوَرِقَ بِالْوَرِقِ إِلاَّ وَزْنًا بِوَزْنٍ مِثْلاً بِمِثْلٍ سَوَاءً بِسَوَاءٍ  

Do not sell a dinar for two dinars and one dirham for two dirhams.  

أَنَّ رَسُولَ اللَّهِ ﷺ قَالَ لاَ تَبِيعُوا الدِّينَارَ بِالدِّينَارَيْنِ وَلاَ الدِّرْهَمَ بِالدِّرْهَمَيْنِ