Ambrose of Milan — as excerpted in the Catena Aurea on Luke 1:30-33

“It was said also of John, that he shall be great, but of him indeed as of a great man, of Christ, as of the great God. For abundantly is poured forth the power of God; widely the greatness of the heavenly substance extended, neither confined by place, nor grasped by thought; neither determined by calculation, nor altered by age.”