Origen

“ There are certain kings of the earth, and the sons of these do not pay toll or tribute; and there are others, different from their sons, who are strangers to the kings of the earth, from whom the kings of the earth receive toll or tribute. ”

“ And among the kings of the earth, their sons are free as among fathers; but those who are strangers to them, while they are free in relation to things beyond the earth, are as slaves in respect of those who lord it over them and keep them in bondage; as the Egyptians lorded it over the children of Israel, and greatly afflicted their life and violently held them in bondage. [2] It was for the sake of those who were in a bondage, corresponding to the bondage of the Hebrews, that the Son of God took upon Him only the form of a slave, [3] doing no work that was foul or servile. ”