Al-Isra: 60
{And when We said to you, "Indeed, your Lord has encompassed the people."}
Remember when We revealed to you that your Lord has encompassed the Quraysh. This means: We gave you glad tidings of the Battle of Badr and victory over them. This is confirmed by His saying: "The assembly will be defeated and they will turn their backs" (Al-Qamar: 45), and "Say to those who disbelieve, 'You will be overcome and gathered together'" (Al-Imran: 12), and other such verses. He spoke of it as if it had already occurred and been realized, consistent with His habit in informing [the Prophet].
When the two armies met on the day of Badr, the Prophet (ﷺ) was in the shelter with Abu Bakr (may Allah be pleased with him), supplicating: "O Allah, I ask You for Your covenant and Your promise." Then he went out wearing his armor, inciting the people and saying: "The assembly will be defeated and they will turn their backs." Perhaps Allah had shown him their places of death in his dream.
He used to say when he reached the water of Badr: "By Allah, it is as if I am looking at the places of death of these people," gesturing to the ground and saying, "This is the place of death of so-and-so, and this is the place of death of so-and-so." The Quraysh heard of what was revealed to the Messenger of Allah (ﷺ) regarding the affair of Badr and what he was shown in his dream of their deaths, so they laughed, mocked, and hastened it in derision.
When they heard his saying: "Indeed, the tree of Zaqqum is the food of the sinful" (Ad-Dukhan: 43), they made it a mockery, saying: "Muhammad claims that Hell burns stones, then says trees grow in it!" Those who said this did not estimate Allah with His true estimation. They did not deny that Allah could create a tree of a nature that fire does not consume. Consider the fur of the Samandal—a small creature in the lands of the Turks from which napkins are made; when they become dirty, they are thrown into the fire, the dirt vanishes, and the napkin remains intact, untouched by the fire. You see the ostrich swallow embers and pieces of iron heated like embers, yet it is not harmed. Closer still: He created fire within every tree, yet it does not burn it; so why deny that He could create a tree within fire that it does not burn?
The meaning is: Signs are sent to frighten the servants. These people were frightened by the punishment of this world, which was the slaughter at Badr. What We showed you in your dream after the revelation was nothing but a fitna (trial) for them, as they took it as a mockery. They were frightened by the punishment of the Hereafter and the tree of Zaqqum, yet it had no effect on them. Then He said regarding them: "And We frighten them"—meaning with the terrors of this world and the Hereafter—"but it increases them in nothing but great tyranny." How, then, would a people in this state be frightened by the sending of the signs they demand?
It is said: The "vision" (ru'ya) refers to the Night Journey (Al-Isra). Those who say the Night Journey was in a dream rely on this, while those who say it was in a state of wakefulness interpret the "vision" as "seeing" (ru'ya). It is also said that He called it a "vision" based on the words of the deniers who said to him: "Perhaps it is a vision you saw, or a fantasy imagined to you," out of their disbelief. Just as He calls things by the names used by the disbelievers, such as: "He turned to their gods" (As-Saffat: 91), "Where are My partners?" (An-Nahl: 27), and "Taste! Indeed, you are the honorable, the noble" (Ad-Dukhan: 49).
Others say: It is his vision that he would enter Mecca. Or that he saw in a dream that the children of Al-Hakam were jumping on his pulpit like children playing with a ball.
If you ask: Where is the tree of Zaqqum cursed in the Quran? I say: It is cursed where its consumers—the disbelievers and the oppressors—are cursed, for the tree itself has no sin to be cursed in reality; it is described as cursed metaphorically through the cursing of its owners. It is also said that Allah described it as cursed because cursing means distance from mercy, and it is at the root of Hell, the furthest place from mercy. The Arabs say of every detestable, harmful food: "cursed." I asked some of them, and they said: "Yes, the cursed food is the poisonous, ruined one." Ibn Abbas said: It is the kushuth (dodder) that twines around trees and is put into drinks. It is also said: It refers to Abu Jahl. It is recited as wa-sh-shajaratu-l-mal'unatu (in the nominative case), as a subject with an omitted predicate, as if to say: "And the tree cursed in the Quran is likewise."