Quran

The greatest terror is the immense turmoil of the Day of Judgment and Resurrection. Alhasan said: "It is the time when people will be commanded to Hellfire." Ibn Jurayj , Saeed bin Jubair, and Al-Dhahhak said: "It is the time when Hellfire will be slammed shut on its dwellers, and death will be slaughtered between Paradise and Hellfire." Al-Qurtubi: 14/295.
Question: The believers will not be grieved by the greatest terror in the Hereafter. Why?

In Sahih Muslim, Ibn Abbas (k) said: The Messenger of Allah (ﷺ) stood up to give an admonition and said: "O people, you will be gathered to Allah, bare-footed, naked and uncircumcised." Then he recited this verse: (Just as We originated the first creation, so We will bring it back. That is Our binding promise, which We will surely do). Ibn Ashur: 17/161.
Question: In light of this verse, explain how the Prophet (ﷺ) used to admonish people.

(The land), in general, means the lands of the east and west. It is also said: The holy land. Moreover, it is said: The land of Paradise, but the first interpretation is more likely. (Righteous servants) are the Muslim nation of Muhammad (ﷺ), for they are praised in this verse. This is also informing about unseen events that later became true when Muslims conquered the east and west of the land. Ibn Juzay: 2/46.
Question: What are the traits of those whom Allah promised to make them inherit the land?

Ibn Abbas (k) said: "It means the lands of the disbelievers that will be conquered by Muslims, and this is a decree of Allah to empower the religion of Islam and Muslims." Al-Baghawi: 3/196
Question: This verse contains a glad tidings to the righteous people. What is it?

In general, the meaning is: Allah had mercy on the worlds by sending our master, Muhammad (ﷺ), because he came with the great joy and salvation from eternal misery. At his hands, his followers attained much good in this life and in the Hereafter; he taught them after they were ignorant, and guided them after being strayed. Ibn Juzay: 2/46.
Question: How did the Prophet (ﷺ) become a given mercy?

If it is said: He is a mercy to the worlds, but the disbelievers did not receive that mercy? The answer can be in two ways: First: The disbelievers would have received mercy had they believed in him, but they were the ones who abandoned the mercy after they were exposed to it. Second: They received mercy because of him since they were not punished swiftly like the previous disbelievers who were destroyed by the deluge, the great cry, and akin to it. Ibn Juzay: 2/46.
Question: What is the answer to the saying that (a mercy to the worlds) is general, yet the disbelievers did not receive the mercy?

(And We have not sent you [O Prophet] except as a mercy to the worlds), Ibn Abbas (k) said: "The mercy has been fulfilled in this life and in the Hereafter for those who believed in him; for those who did not believe in him, they were spared the punishment which struck the ones before them." Al-Tabari: 18/552.
Question: How did our Prophet (ﷺ) become a mercy to the believers and disbelievers?