Tertullian

I find it was in their foresight of all this, that the heavenly intelligences gazed with admiration on "the Jerusalem which is above," and by the mouth of Isaiah said long ago: "Who are these that fly as clouds, and as doves with their young ones, unto me? " Now, as Christ has prepared for us this ascension into heaven, He must be the Christ of whom Amos spoke: "It is He who builds His ascent up to the heavens," even for Himself and His people.