A partner of mine sold some Dirhams on credit in the market. I said, "Glorified be Allah! Is this
legal?" He replied, "Glorified be Allah! By Allah, when I sold them in the market, nobody objected to
it." Then I asked Al-Bara' bin `Azib (about it) he said, "We used to make such a transaction when the
Prophet came to Medina. So he said, 'There is no harm in it if it is done from hand to hand, but it is
not allowed on credit.' Go to Zaid bin Al- Arqam and ask him about it for he was the greatest trader of
all of us." So I asked Zaid bin Al-Arqam., and he said the same (as Al-Bara) did."
Sahih al-Bukhari Book 63, Hadith 164