of Allah.” What is meant here by the remembrance of Allah is the sermon and the prayer. In the sermon Allah is invoked through the tashahhud, the citation of legal rulings, words of admonition, and the like; and as for the prayer, its remembrance of Allah is self-evident. He then says, “and leave off trade,” meaning: stop buying and selling. Hence, once the call to Friday prayer is given, buying and selling become forbidden to anyone upon whom Jumuʿah is obligatory, though they remain permissible for those who are not required to attend, such as women. For the person on whom Friday prayer is due, trading is unlawful, and should he engage in it the sale is invalid—even if he is already on his way to the mosque, hears the adhan, and concludes a deal with a companion. Such a sale is void: the goods do not pass to the purchaser, nor does the price become the seller’s property, because it is null. Everything Allah has prohibited is invalid, in keeping with the Prophet’s saying ﷺ: “Every condition that is not found in the Book of Allah is invalid.”

His words, “O you who believe, when the call is made for the prayer on Friday, hasten to the remembrance of Allah,” also include the traveler who happens to be in town. If he hears the Friday adhan he must attend, for he is a believer—so who has exempted him? Should he claim, “I am traveling,” we ask, “Are you not a believer?” When he answers, “Yes,” we say to him: listen—“O you who believe, when the call is made for the prayer on Friday, hasten to the remembrance of Allah and leave off trade; that is better for you.” It is better for you than commerce, for it establishes one of Islam’s public rites and fulfills an obligation, and is therefore superior to trade. “If you but knew” means: if you possess knowledge, then recognize that it is better. This conditional phrase is meant to urge the abandonment of trade and prompt attendance at the Friday prayer.