Al-Muwatta Hadith 31.69

Yahya related to me from Malik that he had heard that the Messenger of Allah, may Allah bless him and grant him peace, forbade 'selling and lending.' Malik said, "The explanation of what that meant is that one man says to another, 'I will take your goods for such-and-such if you lend me such-and-such.' If they agree to a transaction in this manner, it is not permitted. If the one who stipulates the loan abandons his stipulation, then the sale is permitted." Malik said, "There is no harm in exchanging linen from Shata, for garments from Itribi, or Qass, or Ziqa. Or the cloth of Herat or Merv for Yemeni cloaks and shawls and such like as one for two or three, from hand to hand or with delayed terms. If the goods are of the same kind, and deferment enters into the transaction, there is no good in it." Malik said, "It is not good unless they are different, and the difference between them is clear. When they resemble each other, even if the names are different, do not take two for one with delayed terms, for instance two garments of Herat for one from Merv or Quhy with delayed terms, ortwo garments of Furqub for one from Shata. All these sorts are of the same description, so do not buy two for one, on delayed terms." Malik said, "There is no harm in selling what you buy of things of this nature, before you complete the deal, to some one other than the person from whom you purchased them if the price was paid in cash."