And, in the first part, it says:
For, behold, there are rocks from which streams gush forth;
Through recalling with this part rivers like the blessed Nile and the Tigris and Euphrates, which gush up out of mountains, the Qur'an makes understood the miraculous fashion rocks receive the creational commands and are subjugated to them. It infers the following meaning to vigilant hearts: it is certainly not possible that the mountains could be the actual source of such mighty rivers. For let us suppose the water was cut completely and the mountains each became a conical reservoir, they would only persist a few months before losing the balance to the swift and abundant flow of those large rivers. And the rain, which penetrates only about a metre into the earth, would not be sufficient income for that high expenditure. This means that the springs of these rivers are not something ordinary and natural arising from chance, but that the All-Glorious Creator makes them flow forth from an unseen treasury in truly marvellous fashion.
Thus, alluding to this mystery and stating this meaning, it is narrated in a Hadith: "Each of those three rivers is a drop from Paradise which continuously issues forth from Paradise, as a result of which they are sources of abundance." And in another it is said: "The source of these three rivers is from Paradise."7 The truth of these narrations is this: since physical causes are not capable of producing their abundant flow, their sources must be in an unseen world and must arise from a treasury of mercy; the equilibrium between their incomings and outgoings is maintained in this way.
Thus, through inferring this meaning, the All-Wise Qur'an gives the following instruction: O Children of Israel and Sons of Adam! With your hardness of heart, unfeelingness, and heedlessness you disobey and close your eyes to the commands and light of knowledge of the Pre-Eternal Sun, One so Glorious that He makes flow forth from the mouths of common, lifeless rocks mighty rivers like the blessed Nile, which transforms Egypt into a paradise and produces witnesses to His unity for the universe's heart and earth's mind as eloquent as the force, appearance, and abundant flow of those mighty rivers, and makes them flow to the hearts and minds of jinn and men.
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7.Muslim, Janna, 26; Musnad, ii, 289,440; al-Munawi, Fayd al-Qadlr, vi, 381.