Abu Uthmaan al-Saaboonee (d. 349H) said:
Abu Alee al-Husayn bin al-Fadl al-Bajlee (rahimahullaah) was asked about al-Istiwaa, it was said to him, "How did He ascend over His Throne?" So he said, "We only know of the news about the unseen to the extent of what has been revealed to us (through revelation). And Allaah, lofty be His remembrance, has informed us that He arose over His Throne, but He did not inform us how He arose over."
Aqidah al-Salaf wa As-haab al-Hadeeth (p. 182)
Note: It is from the taqwa of Allaah to affirm whatever He affirmed for Himself without delving into how, as that is from the unseen for which we have been given no knowledge. Just as it clashes with the taqwa of Allah to distort His speech and claim that istiwaa means isteelaa (conquering) and other such distortions of the Jahmiyyah who deny His attributes and actions.
Translated by Abu Iyaad (@abuiyaadsp)