Sforno on Deuteronomy 33:25/ספורנו על דברים ל״ג:כ״ה

1ברזל ונחושת מנעלך וכימיך דבאך, may your door bolts be iron and copper, and your security last all your days.אין כאל ישורון, after Moses had completed his prayer concerning the tribes, he began blessing Israel as a whole.You, who are also known as Yeshurun, wear this title due to the nature of your power, אל, being different from all the other nations in two vital aspects. 1) other nations will not covet your land or try to invade it as they are afraid, something that proved true during the entire reign of Joshua and while any of the elders who were his advisers remained alive. (compare Joshua 24,31). Moses describes the land during that period as if bolted securely with heavy metal bolts, i.e. ברזל ונחושת מנעלך. 2) Your kingdom will not experience constant ups and downs such as the kingdoms of other nations whose position in the world constantly changes. כימיך דבאך, your position among the nations will be constant. The reason why I am certain that my blessing will materialise is that אין כא-ל רוכב שמים וארץ, no one else has a G’d that rides the heavens and the earth. Moses develops a theological/philosophical concept that contradicts that of the nations of the world, even those who recognise a supreme G’d who has created the universe. In their estimation, such a G’d would not bother to constantly stoop down to earth to see what goes on there, i.e. “ride both the heavens and the earth.” These nations believe that such matters must be left to delegates, such as the constellations of the stars, horoscopes, etc.