The Messenger of Allah—peace and blessings be upon him—said, “The finest day on which the sun has ever risen is Friday.” The reason is that on Friday the creation of all beings was completed; on that very day Adam was created, then admitted into Paradise and later sent down from it, and on it the Final Hour will be established. All of this occurs on Friday, making it the most excellent of days. It was also the last of the six days of creation, during which the heavens, the earth, and everything within them were brought into existence.
“Then He rose over the Throne.” The particle thumma (“then”) here conveys both conjunction and chronological sequence, indicating that His rising over the Throne took place after He had created the heavens and the earth. This act is one of the divine action-attributes that Allah performs whenever He wills.
The verb istawā means “ascended” and “rose high.”
The Throne (ʿarsh) is the roof of the created universe. In Arabic usage the word refers to a couch or throne—specifically, a bedstead with legs—borne by the angels. It is the greatest and loftiest of all created things.
Istiwaʾ is an action-attribute of Allah that befits His majesty; it is nothing like a creature mounting another creature. Moreover, He has no need of the Throne, for He alone upholds the Throne.