I asked Imam (as) about currency exchange, and I said to Imam (as): "Sometimes during travel, the caravan may hurry, and we are unable to find the Damascene and Basran currencies. However, only the Damascene and Basran currencies are accepted in Nishapur. Imam (as) asked: 'What is the caravan?' I said: 'It refers to a group of people who travel together and prepare for departure. If they hurry, they may not find the required currencies, so we sell them the lower-quality coins, exchanging 1,050 of these for 1,000 Damascene coins.' Imam (as) said: 'There is no good in this. Why don't you add gold to it to account for the excess amount?'" I said to Imam (as): "Can I buy 1,000 and a dinar with 2,000 dirhams?" Imam (as) said: "There is no harm in it. My father (as) was bolder than us towards the people of Medina. He used to do this, and they would say it is merely a tactic. They would claim that if a man brought a dinar, he would not receive 1,000 dirhams, and if he brought 1,000 dirhams, he would not receive a dinar." Then Imam (as) used to say: 'What an excellent thing it is to flee from the unlawful to the lawful.'"