Regarding the categories of vendition and the legal and illegal purchase and vendition, all the laws are arranged for saving the nourishment of the servants (of God) and achieving their prosperity concerning their food, drink, dress, marriage, property, and the dependent affairs. It is licit for them to traffic in all the profitable matters that are indispensable for them and achieve their prosperity. Vendition, purchase, possession, exploitation, endowment, and loan of the above-mentioned matters are licit.
The illegality of transaction includes every matter that is prohibited and causes corruption by way of eating, drinking, earning, marrying, possessing, using, endowing, or loaning it or any matter that causes corruption, such as usurious vendition, which causes corruption, and vendition of corpses, blood, pork, meat and skins of beasts including wild animals and birds, wine, or any other impure thing. These matters are illicit and prohibited. God has prohibited eating, drinking, dressing, possessing, using, and disposing of these things because this causes corruption. In other words, any disposition of such things is illegal. In addition, every vendition of illegal amusement is illegal. It is illegal and prohibited to vend, purchase, use, possess, endow, loan, or dispose in any prohibited substance that is used for seeking the favors of other than God or supporting atheism and polytheism by all ways of acts of disobedience or any way that supports any path of deviation or wrong or weakens the right, except in cases of necessity.