—the dawn prayer that followed a night of rain. When he finished the prayer, he turned to the people and asked, “Do you know what your Lord has just declared?” They replied, “Allah and His Messenger know best.” He posed the question only to make them attentive, for asking questions awakens the listener.

They said, “Allah and His Messenger know best,” and this is the courtesy required of anyone who is asked about something he does not know in matters of religion. With regard to worldly, pre-ordained affairs one should not add, “and His Messenger knows best,” because the Prophet—peace and blessings be upon him—does not know the unseen. So, for example, if someone asks, “Do you think it will rain tomorrow?” you should answer, “Allah knows best,” not “Allah and His Messenger know best,” for the Messenger does not possess such knowledge. But if someone asks, “Is this action lawful or unlawful?” you may say, “Allah and His Messenger know best,” because the Prophet has knowledge of the sacred law.

The Companions therefore replied, “Allah and His Messenger know best,” which is proper etiquette. He then said—that is, the Prophet reported that Allah had said—“This morning some of My servants rose as believers in Me while others rose as disbelievers. Whoever said, ‘We were given rain by the favor and mercy of Allah,’ is a believer in Me and a disbeliever in the stars. Whoever said, ‘We were given rain by the rising of such-and-such a star,’ is a disbeliever in Me and a believer in the stars.”

Here the preposition “by” expresses causation: if you attribute the rainfall to a star and say, “This star is a star of blessing and goodness that brings the rain,” that is forbidden and amounts to disbelief in Allah, for assigning an effect to its perceived cause while forgetting the true Cause—Allah, exalted is He—is an act of unbelief. If, however, you say, “We were given rain by the favor and mercy of Allah during this star-phase,” there is no harm in that, because