"'And from this it is evident "'that there was a time when the Son was not. "'It therefore necessarily follows "'that he, the Son, had his substance from nothing.'" So he's drawing a distinction between the essence of the Father and the Son manifested as Jesus Christ. Now, this is very controversial because even his own bishop in Alexandria viewed the Father and the Son to be of the same substance. Now, today you might say, hey, isn't this just wordplay? It feels like it's semantic, which is really debating around the meaning of words. But at the end of the Roman Empire and as we get into the Middle Ages, this was a major issue of philosophical and it would sometimes bleed over into political debate.