at that time from heaven to earth—is Allah’s sunna regarding all His creation, and an informing from Him thereby to those whom He informed about in the beginning of this Sūra by what He informed about them in His saying (1): {Indeed, those who disbelieve - it is all the same for them whether you warn them or do not warn them - they will not believe} [Sūrat al-Baqara: 6], and in His saying: {And of the people are some who say, "We believe in Allah and the Last Day," but they are not believers} [Sūrat al-Baqara: 8], and that His ruling regarding them—if they repent to Him, turn back, and follow the clarification that came to them from Allah at the tongue of His Messenger Muḥammad ﷺ—is that they are with Him in the Hereafter among those over whom there is no fear, nor shall they grieve; and that if they perish in their disbelief and error before turning back and repenting, they will be among the people of Hellfire, abiding eternally therein.

And His statement: "Then whoever follows My guidance," means: whoever follows My clarification which I brought upon the tongues of My Messengers, or along with My Messengers (2). As:

795- Al-Muthannā narrated to us, he said: Ādam narrated to us, he said: Abū Jaʿfar narrated to us, from al-Rabīʿ, from Abū al-ʿĀliya: {Then whoever follows My guidance}, meaning My clarification. (3)

And His statement: "No fear shall come upon them," means they are secure amidst the terrors of the Resurrection from Allah’s punishment, not fearing His torment, because of their obedience to Allah in the world and their following of His command, His guidance, and His path; "Nor shall they grieve" on that Day over what they left behind after their death in the world. As:

796- Yūnus ibn ʿAbd al-Aʿlā narrated to me, he said: Ibn Wahb informed us, he said: Ibn Zayd said: "No fear shall come upon them," he says: No fear shall be upon you ahead of you (4).

And there is nothing greater in the breast of one who dies than what comes after death. So He made them secure from it and consoled them regarding the world, saying: "Nor shall they grieve."