Whoever sees an infant crying hard, then sees his mother place the child at her breast so that he immediately settles, knows with certainty that the calming came from the milk. Although abstract possibilities may be entertained for the class as a whole, they often do not apply to a particular, concrete case.
The same applies to supplications. A believer may call upon Allah and then witness with his own eyes the very thing he asked for, even though none of the usual means exist; or he may perform an act of that nature and find it fulfilled. Such was the case with al-Alaʾ ibn al-Hadrami (may Allah be pleased with him). He once said, “O All-Knowing, O Forbearing, O Most High, O All-Great, give us to drink,” and on a day of intense heat rain poured down upon them—rain that did not extend beyond their camp. On another occasion he said, “Carry us across,” and they walked over a great river, their mounts’ lower legs not even getting wet. Likewise, when Ayyub al-Sakhtiyani struck a mountain once with his foot for the sake of his companion, a spring gushed forth; he drank from it and it then disappeared.
Thus, calling upon Allah alone, without partner, is affirmed as beneficial by the revealed texts, by sound reason, and by experiences so numerous that only Allah could count them. You will find that most believers have prayed to Allah for matters whose outward causes were absent for them, whereupon Allah brought those very things into being for them