digging trenches for war, but are constructing permissible buildings: is singing lawful for them in order to help them endure the work? Yes, that is permissible.

What matters is that when the author says, “singing,” he means prohibited singing—either prohibited in itself or because it is accompanied by some prohibited act. We say, “a prohibited act,” because this is broader: it includes instrumental music, revelry, dancing, and the like.

His statement, “or makes his house into a church or a place for selling wine,” means that if someone rents another person’s house in order to hold Christian religious rites there, making it into a church, then the lease is prohibited, because Allah the Exalted says:

“And do not cooperate in sin and transgression.” [al-Ma'idah 5:2]

The same applies if he rents it in order to sell wine, tobacco, satellite channels, or televisions. The lease is prohibited if most purchasers of televisions use them for prohibited purposes, because television contains both prohibited and non-prohibited material; it is a device which a person uses as he wishes.

But if he rents the house in order to live in it, and he is a Christian who then makes a place of worship in the house, the lease is valid. At the time of the contract, he contracted only for a permissible purpose—residence. The sin in this case takes place in the house, but he did not rent the house for that purpose.

Likewise, if someone rents a house to another person and he then installs satellite channels in it, bringing in every corrupt channel, then the ruling is as follows: if he rented the house for this purpose, the lease is prohibited and invalid. But if he rented it as a residence and subsequently installed these things in it, there is no blame. However, when the contract ends—that is, when the lease period has ended—he says