Why does 2:74 use "or"?

Question

I first found this verse while reading the context of a verse. I do not know if it's a feature of the Arabic language. Qur'an 2:74 (emphasis mine):

2:74 ثُمَّ قَسَتْ قُلُوبُكُم مِّنۢ بَعْدِ ذَٰلِكَ فَهِىَ كَٱلْحِجَارَةِ أَوْ أَشَدُّ قَسْوَةًۭ ۚ وَإِنَّ مِنَ ٱلْحِجَارَةِ لَمَا يَتَفَجَّرُ مِنْهُ ٱلْأَنْهَـٰرُ ۚ وَإِنَّ مِنْهَا لَمَا يَشَّقَّقُ فَيَخْرُجُ مِنْهُ ٱلْمَآءُ ۚ وَإِنَّ مِنْهَا لَمَا يَهْبِطُ مِنْ خَشْيَةِ ٱللَّهِ ۗ وَمَا ٱللَّهُ بِغَـٰفِلٍ عَمَّا تَعْمَلُونَ ٧٤
Then your hearts became hardened after that, being like stones or even harder. For indeed, there are stones from which rivers burst forth, and there are some of them that split open and water comes out, and there are some of them that fall down for fear of Allāh. And Allāh is not unaware of what you do. — Saheeh International

The word used is أَوْ which does mean "or". Why does it use or about "like stones or harder" even though ALLAH is all knowing, thus meaning that HE doesn't doubt about what is actually true?

how is this explained?

Answer 1

"You" is the plural you here.

• Some of "you" have hearts that have become hardened, being like stones.
• Some of "you" have hearts that have become hardened, even harder.

"Or" doesn't indicate doubt here. It's no different a construction than, say, "All people, big or small, are welcome here," where the "or" just indicates that the group in question includes those with both the first (hardened like stones, big) attribute as well as the second (hardened even harder, small).

Were it Allah's will, I'm sure He could have revealed by name every person whose heart was hardened being like stones, and every person whose heart was hardened even harder. I for one am glad that He did not choose to do that, Surat al-Baqarah is already long enough as it is.

Answer 2

It is a style of speech and likes of it are used throughout the Quran not just in 2:74. e.g. in Quran 53:9, Quran 37:147, Quran 16:77 etc.

Answer 3

This is a grammar point. "أَوْ" has different uses in Arabic. ref One of its uses refers to types and varieties. In the verse it comes from stone or harder. According to the verses, stones have different types. Some rocks are impenetrable. But water comes out of some stones which aren't impenetrable. ref