Sentence:  Thus the image of <WSD>God</WSD> is that which makes a man a man and not an oyster ; the similitude of God , by contrast , is that which makes a man a child of God and not merely a rational creature . 
Meaning of the word marked with <WSD> tags:  the supernatural being conceived as the perfect and omnipotent and omniscient originator and ruler of the universe; the object of worship in monotheistic religions