Adam Clarke on Matthew 4:5

Pinnacle of the temple - It is very likely that this was what was called the στοα βασιλικη, the king's gallery; which, as Josephus says, "deserves to be mentioned among the most magnificent things under the sun: for upon a stupendous depth of a valley, scarcely to be fathomed by the eye of him that stands above, Herod erected a gallery of a vast height, from the top of which if any looked down, he would grow dizzy, his eyes not being able to reach so vast a depth." - Ant. l. xv. c. 14. See Dr. Lightfoot on this place.