Quran

Whoever invokes others besides Allah is like a thirsty person who calls the water from a distance to come to his mouth so he can drink but he is unable to obtain it with his words (through calling), and stretches out his hand for the water but the water never comes to him because it does not respond. Al-Qurtubi: 12/42-43.
Question: Allah likens the polytheist to a thirsty person. Explain.

Because of the falseness of those on whom they call besides Allah, thus, their worship and supplication are invalid since the means become invalid if the end is invalid. Al-Saadi: 415.
Question: Why is the supplication of the disbelievers in vain? What is the link between the means and the end with respect to truth and falsehood?

Everything prostrates according to its situation, as Allah says, (There is not a thing that does not glorify Him with praise, but you do not understand their glorification) [17: 44]. Al-Saadi: 415.
Question: How do all things in the heavens and on earth prostrate to Allah?

The wisdom behind prostrating when reciting this verse is that the Muslim counts himself to be among those who prostrate to Allah willingly, which is a practical admission of his submission to Allah, the Almighty. Ibn Ashur: 13/112.
Question: What is the wisdom behind prostrating when reciting this verse?

Allah likens knowledge to a water falling from the sky because knowledge revives the hearts just as water revives the bodies. He likens the hearts to valleys since they hold knowledge just as valleys hold water. A heart may hold much knowledge, and a valley may hold much water. Similarly, another heart may hold less knowledge, and another valley may hold less water. Ibn Taimyah: 4/86.
Question: Hearts differ in holding knowledge. Explain in light of the verse.

Allah presents an example of the truth and falsehood, and He likens disbelief to a foam on top of a torrent, so it dissipates and becomes stranded by the edges of the valley, then, it is blown away by the wind, and that is how disbelief goes away and perishes. These two examples are presented by Allah: Steadiness of truth, and vanishing of falsehood. Even if falsehood rises to the top in some cases, it will eventually vanish like the foam and residue do. Al-Qurtubi: 12/48-51.
Question: How does the Quran present the outcomes of truth and falsehood?

(The worst reckoning), Ibrahim Al-Nakhai said: It means that a person is judged on all of his sins, nothing will be forgiven. Al-Baghawi: 2/523.
Question: What will the worst reckoning be like on the Day of Resurrection?