For they [be] thy people, and thine inheritance, which thou broughtest forth out of Egypt, from the midst of the furnace of iron:
Ver. 51. For they be thy people.] Culled and called out of the rest of the world. Thou hast avouched them for thine; and they have avouched thee for their God.
From the midst of the furnace of iron.] Where they were grievously afflicted, and by those afflictions melted and made more malleable.