Why does Papa beat Mama, Jaja and Kembili

Papa isn't a nice person; he is rather sadistic. He is a devout Catholic who expects nothing less than perfection from his family. Papa punishes his wife and children in order to correct their behavior. Papa is beloved in his community but is estranged from his own father and his traditional African culture.

Papa is a strict authoritarian who has impossibly high standards for both his children and wife. He punishes them whenever he perceives they have done something wrong. He beats them up because he thinks thats the only way they get to justify the wrong deeds they did. He also thinks that corporal punishment is much better to use against his children because the same also happened to him when he misused his body when he was young and he was forced to dip his hands in hot water. So Eugene is just trying to mould his familys' behavior but in a more wrathful way.