Did you not see to your Lord? Did we not look at the creation of your Lord and His power? The meaning of extending the shadow is that He made it extend and spread so that people benefit from it. If He had willed, He would have made it stationary, that is, attached to the base of every shade from a mountain, building, or tree, not spread out, so that no one would benefit from it. The spreading and extending of the shadow is called movement from Him, and the lack of it is called stillness. The meaning of the sun being a guide is that people use the sun and its conditions in its course to understand the conditions of the shadow, whether it is fixed in a place, moving, expanding, or contracting. They base their need for shade and their independence from it according to that. Its gradual retraction means that it is replaced by the brightness of the sun. In the authentic reports, it is said that the brightness refers to the sun. In the hadith, it is mentioned, 'Let none of you sit between the brightness and the shade,' for it is the sitting place of the devil. The retraction is gradual, that is, slowly. In this gradual retraction, there are countless benefits that cannot be counted or enumerated. If it were to retract all at once, most of the people's needs for shade and the sun would be disrupted. If you say: Then in these two instances, what is its position? I say: Its position is to indicate the superiority of the three matters: the second is greater than the first, and the third is greater than both, likening the distance between them in virtue to the distance between events in time. Another point is that the extension of the shadow when the sky was built is like a dome that was struck, and the earth was spread beneath it, so the dome cast its shadow on the earth, covering what is in its surface. This is due to the absence of light. If He had willed, He would have made it stationary and settled in that state. Then He created the sun and placed it over that shadow, that is, He made it a guiding leader for it, just as a guide is followed on the road. It increases and decreases, extends and contracts, then He replaced it with it, retracting it easily and gently, not with difficulty. It is possible that He means: its retraction at the Day of Resurrection by retracting its causes, which are the celestial bodies that maintain the shadow, so He has mentioned its annihilation by the annihilation of its causes, just as He mentioned its creation by the creation of its causes. His saying: 'We have retracted it to Us' indicates this, as does His saying: 'easily,' just as He said: 'That is an easy gathering for Us.'