The reason the heavens come in the plural form and the earth in the singular form
Machine translationRead the Arabic original
Question:
I ask Allah to do you good. Your Eminence, father, the questioner asks: Is there an explanation for the heavens coming in the plural form and the earth in the singular form?
Answer:
[At-Talaq 65:12] So Allah, and the earth is seven, seven earths. Yes, but they are sometimes summarized. He said, "The earth," summarizing it, and it encompasses the seven layers. Yes. And likewise, whoever usurps a span of the earth will be encircled with it on the Day of Resurrection from the seven earths. Yes. So the earth is seven, just like the heavens. Yes.
I ask Allah to do you good. Your Eminence, father, the questioner asks: Is there an explanation for the heavens coming in the plural form and the earth in the singular form?
Answer:
It is Allah who has created seven heavens and of the earth, the like of them
اللَّهُ الَّذِي خَلَقَ سَبْعَ سَمَاوَاتٍ وَمِنَ الْأَرْضِ مِثْلَهُنَّ
Source
تفسير حزب المفصل، تفسير سورة الحديد : الآيات [ 1 - 7 ] — islamhouse.com (49:59)
The Arabic text is a machine transcription of the audio recording.