Sayyiduna Abdullah bin Amr (may Allah be pleased with them both) narrates that the Messenger of Allah (peace and blessings be upon him) said: "A loan and a sale are not permissible together, nor are two conditions in one sale permissible. It is not permissible to take profit from something for which a person does not bear the risk of loss, nor is it permissible to sell something which is not in your possession."