“I once said to abu al-Hassan (a.s.), ‘I like to travel to certain areas of the mountains.’ He (the Imam) said, ‘This year people will not be able to avoid difficult times.’ I then said, ‘I pray to Allah to keep my soul in service for your cause, if we sell to them goods on credit with deferred payment it is more profitable. He (the Imam) said, ‘Sell to them for one year deferred payment.’ I asked, ‘Can we defer payment for two years?’ He (the Imam) said, ‘Yes, you can do so.’ I then asked, ‘Can we defer payment for three years?’ He (the Imam) said, ‘No, you cannot do so.’”