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In this great postcolonial classic, Obierika seems to act as a kind of foil to Okonkwo through his differences. Whilst Okonkwo is a man of strength and action, Obierika is a much more thoughtful person. Consider his response to Okonkwo's exile:
Obierika was a man who thought about things. When the will of the goddess had been done, he sat down in his obi and mourned his friend's calamity. Why should a man suffer so greviously for an offence he had commited inadvertently?
Thus we can see how Obierika cares for his friend and mourns his misfortune. He helps Okonkwo in readying himself for his exile, and also visits his friend whilst he is away from his friends and village. It is Obierika who tells Okonkwo of the arrival of the missionaries and the impact on the village. Note, too, how when the exile of Okonkwo draws to a close, it is Obierika who builds two huts and sends a message summoning Okonkwo back to the village. Lastly, Obeierika's friendship of Okonkwo is proved in the author giving him the final words to say about Okonkwo's life, acting as a kind of elegy:
Obierika, who had been gazing steadily at this friend's dangling body, turned suddenly to the District Commissioner and said ferociously: "That man was one of the greatest men in Umuofia. You drove him to kill himself; and now he will be buried like a dog..." He could not say any more. His vioce trembled and choked his words.
Note how his anger and the way his voice trembled proves his love and deep friendship of Okonkwo. Throughout the novel, Obierika acts as a friend and support to Okonkwo, and thus it is fitting that he has the final word on his friend's life.