[15] [cap.3] Therefore do not doubt either whether that which is more ancient than any existing thing is indescribable, when his very word is not to be mentioned by us according to its proper name. So that we must understand that the expression, "The Lord was seen by Abraham," [16] means not as if the Cause of all things had shone forth and become visible, (for what human mind is able to contain the greatness of his appearance?) but as if some one of the powers which surround him, that is to say, his kingly power, had presented itself to the sight, for the appellation Lord belongs to authority and sovereignty.