John and Stephan have distinctly different values although they are of the same family what point is the author trying to make through his comparison of john kumalo and tephen Kumalo?

Stephan is a kind and just man who believes in the strength of family life and God: Kumalo searches desperately for his son in order to reunite his family, but becomes an activist for social justice and a return to rural life once he learns that his son is responsible for the murder of Arthur Jarvis. The brother of Stephen Kumalo, he is a former carpenter who has become a great political leader in Johannesburg primarily because of his charisma and speaking abilities. Unlike his brother, John Kumalo has forsaken the church and now lives a largely immoral life, having divorced his wife and taken up with a mistress. John Kumalo's son (Matthew) is also responsible in the murder of Arthur Jarvis, but because there is no tangible evidence he betrays Absalom and is acquitted for the murder.