Still others are lands that neither retain water nor put forth any pasture; such are the hearts that take no benefit from the revelation—gaining neither knowledge, nor memorisation, nor action.
The correspondence between lands and hearts is, as you can see, perfectly plain. As for the fitness of likening revelation to rainfall, it is because rain brings life to the earth and to its inhabitants and supplies their material provisions, while revelation gives life to hearts and souls and furnishes the substance of their intangible sustenance.
Likewise, Allah has likened the word of tawḥīd (monotheism) to a goodly tree that yields its fruit at every moment by its Lord’s leave. In the same manner, the tree of tawḥīd is firmly rooted in the heart of its possessor as knowledge, affirmation, faith, and a will that complies with its demands. It bears its fruit—its benefits—unceasingly: wholesome intentions, noble character, righteous deeds, upright guidance, and benefit that touches both its owner and the people around him. Ever ascending toward heaven, it is raised by the sincerity, knowledge, and certitude of the one who holds it.
By contrast, Allah has likened shirk (polytheism)—and the polytheist who takes a deity besides Allah seeking strength, imagining that such a god will bring him benefit or repel harm—to a spider that weaves a house, the frailest and most fragile of dwellings; by building it she only adds weakness to her weakness. So too, the polytheist gains nothing from taking an ally and helper other than Allah except deeper feebleness, for his heart has been cut off from Allah, and whoever’s heart is severed from Allah is overtaken by weakness on every side. His attachment to created beings merely heaps frailty upon frailty: he relies on them, expecting benefit, only to see his hope dashed and his expectation fail.
The believer, on the other hand, is strong through the strength of his faith in Allah, his tawḥīd, and his exclusive attachment to Allah alone—the One who holds command, benefit, and the removal of harm, and who governs every one of his circumstances. He is like a servant who walks straight upon a clear path in word and deed, possessed of a free and unshackled will, liberated from the bondage of created beings, unfettered by them in any respect.
The polytheist, however, is like a deaf-mute slave—dead weight, a burden upon his master; wherever the master directs him, he brings no good, for his heart is chained to created beings and enslaved by them,