It is narrated from Sayyiduna Hakim bin Hizam that I pledged allegiance to the Prophet (peace be upon him) on his blessed hand with the condition that I would not spend the whole night sleeping soundly, but would stand (in prayer). It is narrated from Sayyiduna Hakim that once I submitted in the court of Prophethood: O Messenger of Allah! A man comes to me and wants to buy something from me, but at that time I do not have that thing. Can I buy it from the market and sell it to him? The Prophet (peace be upon him) said: Do not sell that which you do not possess.