Tafsir of Al-Anbiya' 21:103

ﻻ يحزنهم الفزع اﻻكبر

The greatest terror will not grieve them, It was said that; this means death, as was narrated by Abdur-Razzaq from Yahya bin Rabi`ah from Ata.' Or it was said that; the greatest terror refers to the blast of the Trumpet, as Al-`Awfi said narrating from Ibn Abbas and Abu Sinan, Sa`id bin Sinan Ash-Shaybani. This was the view favored by Ibn Jarir in his Tafsir.

وتتلقاهم المﻼيكة هذا يومكم الذي كنتم توعدون

and the angels will meet them, (with the greeting:) "This is your Day which you were promised''. meaning, the angels will greet them on the Day of Resurrection when they emerge from their graves with the words:

هذا يومكم الذي كنتم توعدون

("This is your Day which you were promised''), meaning, hope for the best