trades such as farming, weaving and building, those who practise them must provide their services to them at their fair value, just as they must supply needed property at its fair value. There is no difference between providing property and providing services. Indeed, where providing services causes no harm, there is all the more reason to require their provision in return for compensation. Providing these services is a collective obligation.
A number of scholars, both among our own scholars and others, have stated that the basic trades, such as farming, weaving and building, are a collective obligation.
The precise position is that they are obligatory when needed; when people can do without them, however, they are not obligatory. We have discussed the sale of these services, for those who require their provision require it only in return for compensation, not gratuitously. Thus, this is an obligation to practise a trade for payment because it is needed. I specify “when needed” because Muslims may have no need to practise a trade themselves, owing to the food and clothing they bring in or that are brought to them.
The fundamental principle is that people are obliged to help one another obtain food, clothing and shelter. The ruler may require this and compel people to fulfil it; doing so is not injustice. Indeed, the Lawgiver’s imposition of jihad—which entails risking life and property in order to guide people in their religion—goes much further than any of this. If the courage and generosity that Muslims need are obligatory, how much more so are the exchanges they need? Yet most people do this out of habit, natural inclination and obedience to