{To Him belongs what is in the heavens and what is on the earth and what is between them and what is under the soil}. Abu Raja' al-'Utari said: The soil (al-thara) is the earth that is beneath the water, upon which one rests; He knows what is beneath that soil.
﴿لَهُ مَا فِي السَّمَاوَات وَمَا فِي الأَرْضِ وَمَا بَيْنَهُمَا وَمَا تَحت الثرى﴾ قَالَ أَبُو رَجَاء العطاري: الثَّرَى: الْأَرْضُ الَّتِي تَحْتَ الْمَاءِ الَّتِي يُسْتَقَرُّ عَلَيْهَا؛ فَهُوَ يَعْلَمُ مَا تَحت ذَلِك الثرى