Al-Anbiya 21:104
"Naṭwī al-samāʾa ka-ṭayyi al-sijilli li-l-kutub" — the sky is a parchment scroll opened for writing; on that day it is rolled up.
يَوْمَ نَطْوِى ٱلسَّمَآءَ كَطَىِّ ٱلسِّجِلِّ لِلْكُتُبِ ۚ كَمَا بَدَأْنَآ أَوَّلَ خَلْقٍ نُّعِيدُهُۥ ۚ وَعْدًا عَلَيْنَآ ۚ إِنَّا كُنَّا فَـٰعِلِينَ
On the Day when We fold the heaven, like the folding of a book. Just as We began the first creation, We will repeat it—a promise binding on Us. We will act
Al-Anbiya 21:104 · Translation: talal-itani
Image
"Sijill" in Arabic is a register, a record; "ṭayy" is folding, rolling up. "Kamā badaʾnā awwala khalqin nuʿīduhu" (as We began the first creation, We will return it) — a phrase of return to the original state. The verse traces a symmetrical cycle between the first state of the cosmos and its last.
Observation
In modern cosmology the universe's initial state (a span shorter than seconds after the Big Bang) is modelled as extreme density and temperature within a tiny spatial volume. A thermodynamic reversal (the Big Crunch) has been discussed at the level of hypothesis, but today's observation points toward accelerating expansion — the final state is not settled in the language of observation. The verse speaks of "return to the initial state"; physics has not translated this sentence into observation. Only a contemporary parallel of the image stands beside it.
Exegesis
Al-Qurṭubī (al-Jāmiʿ li-Aḥkām al-Qurʾān) says that "ṭayy" is not the erasure of what is written but the closing of it from view — the cosmos is not cast into nothingness; it is set beside its earlier form by a closing. Al-Rāzī notes that "waʿdan ʿalaynā" (it is a promise upon Us) emphasizes God's self-binding pledge.
Sources
Tafsīr: al-Qurṭubī · al-Jāmiʿ li-Aḥkām al-Qurʾān; al-Rāzī · Mafātīḥ al-Ghayb. Science: cosmology (Big Bang initial state, future state of the universe).