So we awaked them that they might question one another. Said one of them, "How long have ye tarried here?" They said, "We have tarried a day or part of day." They said, "Your Lord knoweth best how long ye have tarried: Send now one of you with this your coin into the city, and let him mark who therein hath purest food, and from him let him bring you a supply: and let him be courteous, and not discover you to any one.