A man who could be the father of his son's flesh, but that did not mean that he was also the father of his spirit. These lines mean that a son can physically look like his father or appear to be similar to him in terms of height, weight and looks but can be different in other aspects. These aspects could be in terms of spirituality, aspirations , dreams and ambitions. The son may have different lifestyle and approach to life. He was born in a different time and different century when socio- economic conditions were quite different. The school he goes to, the friends he had , his socialisation was quite different. As a result of all these factors, the son will be quite different in spirit.