Ata bin Abi Rabah (may Allah have mercy on him) narrates: A man came to Sayyiduna Ibn Abbas (may Allah be pleased with them both) and asked: "What do you say about two (inferior) dirhams being exchanged as equal to one good dirham?" He said: "What harm is there in that? It is just like two camels in exchange for one fat she-camel." At this Sayyiduna Abu Sa'id al-Khudri (may Allah be pleased with him) said: "O Ibn Abbas, are you the one who consumes usury (riba) and feeds it to the people?" He asked: "Who is this?" It was said: "It is Abu Sa'id." He said: "I did not know that anyone who knows my kinship with the Messenger of Allah (peace and blessings be upon him) would dare to speak to me like this." Sayyiduna Abu Sa'id (may Allah be pleased with him) said: "By Allah, I am saying this to you only out of sincere counsel and concern for you. I heard the Messenger of Allah (peace and blessings be upon him) saying: 'Gold for gold, like for like; silver for silver, like for like; dates for dates, like for like; and salt for salt, like for like (is to be sold).'"
Imam al-Tabarani (may Allah have mercy on him) said: "No one narrated this hadith from Matar al-Warraq except Ibrahim bin Tahman."
Hadith Referenceالمعجم الأوسط / باب الألف / 2158
Hadith Takhrij«أخرجه الطحاوي فى «شرح معاني الآثار» برقم: 5754»