It is narrated from Sayyida Aisha Siddiqa (may Allah be pleased with her) that the Messenger of Allah (peace and blessings be upon him) had decided that profit is in exchange for guarantee. Abdullah says that my father, Imam Ahmad bin Hanbal (peace and blessings be upon him), said: I heard from Qaran bin Tamam in 181 AH; in that year, Imam Ibn Mubarak was alive, but then in the same year he passed away.
Hadith Referenceالفتح الربانی / كتاب الفضائل والمناقب / 11614