The 7 Quranic heavens

In answer to the video "Muhammad and Merkabah Mysticism"

The Arabic equivalents of the numbers seven, seventy, and seven hundred are all used, besides quantification, to convey the idea of a very large number in Classical Arabic. The same is the case in other semitic languages, such as Hebrew, as seen even in the Jewish scriptures Prov24:16,26:25etc. It was used in common talk, as in a report attributed to the prophet in which he condemns gluttony by metaphorically speaking of it as eating with seven intestines. There are several examples in the Quran as seen in 9:80,31:27,18:109 or when the Quran speaks of there existing seven earths 65:12. This by the way points to the existance of lifeforms elsewhere in the universe

42:29"And one of His signs is the creation of the heavens and the earth and what He has spread forth in both of them of living beings; and when He pleases He is all-powerful to gather them together".

In 10:66 the entities spread through the heavens are described with the pronoun "man" which is only used for creatures with an intellect, as opposed to "ma" used two verses later that also covers inanimate entities.