Tafsir of Fussilat 41:30

{Then} (thumma): Indicates the delay of "uprightness" (istiqama) from "confession" (iqrar) in rank. Its superiority over confession is because uprightness encompasses the entire matter. Similar to this is His saying: “The believers are only those who believed in Allah and His Messenger, then did not doubt” (Al-Hujurat: 15). The meaning is: then they remained firm upon the confession and its requirements.

From Abu Bakr al-Siddiq (may Allah be pleased with him): "They were upright in action just as they were upright in speech." It is also narrated that he recited this verse and asked, "What do you say about it?" They replied, "They did not sin." He said, "You have taken the matter to its extreme." They asked, "Then what do you say?" He replied, "They did not return to the worship of idols."

From Umar (may Allah be pleased with him): "They remained upright on the path; they did not swerve like the swerving of foxes."

From Uthman (may Allah be pleased with him): "They made their deeds sincere."

From Ali (may Allah be pleased with him): "They performed the obligatory duties."

Sufyan ibn Abdullah al-Thaqafi (may Allah be pleased with him) said: I said, "O Messenger of Allah, tell me something I can hold fast to." He said, "Say: 'My Lord is Allah,' then be upright." I asked, "What do you fear most for me?" The Messenger of Allah (peace be upon him) took hold of his own tongue and said, "This."

{The angels descend upon them} at the time of death with glad tidings. It is said: The glad tidings occur in three places: at death, in the grave, and when they rise from their graves.

{That you should not fear}: "That" (an) is explanatory (meaning "i.e."), or it is the lightened form of the heavy anna. Its origin is "that you should not fear," with the ha being the pronoun of the state (dhamir al-sha'n). In the recitation of Ibn Mas'ud (may Allah be pleased with him): "Do not fear," meaning: they say, "Do not fear."

Fear is distress that occurs due to the expectation of something disliked. Grief is distress that occurs due to its occurrence, through the loss of something beneficial or the attainment of something harmful. The meaning is: Allah has decreed for you security from every distress, so you shall never taste it. It is also said: Do not fear what you are approaching, and do not grieve for what you have left behind.

Just as the devils are the companions and brothers of the disobedient, so too are the angels the allies and beloved ones of the righteous in both abodes.

{You shall have therein}: You shall have whatever you desire.

{As a gift} (nuzul): The provision of hospitality, which is for the guest. Its accusative case is due to it being a state (hal).

{And who is better in speech than one who invites to Allah, does righteousness, and says: "Indeed, I am of the Muslims"?}