A Revelation from Him (Allah) Who has created the earth and high heavens.
means, `This Qur'an, which has come to you, O Muhammad, is a revelation from your Lord. He is the Lord of everything and its King. He is Most Able to do whatever He wills. He created the earth with its low depths and dense regions. He created the lofty heavens with their high altitudes and subtleties.'
It has been reported in a Hadith, which At-Tirmidhi and others graded as authentic, that;
the density of each sky of the heavens is the distance of five hundred years travel and the distance between it and the next heaven is also five hundred years.
Concerning Allah's statement,
الرَّحْمَنُ عَلَى الْعَرْشِ اسْتَوَى