Obierika is Okonkwo’s closest friend; knew Okonkwo’s father, Unoka; and understands Okonkwo’s background. Unlike Okonkwo, Obierika is reflective and thoughtful. He often provides commentary on Okonkwo’s actions and on life in Umuofia. These characteristics make Obierika a foil to the more impulsive Okonkwo. Obierika is less driven to prove himself than Okonkwo, which allows him to see things more clearly. However, Okonkwo rarely heeds Obierika’s advice.

Although Obierika is sympathetic to Okonkwo’s depression over Ikemefuna, he still rebukes Okonkwo for his part in the killing. Obierika detests violence, condemning the ritualistic killing. While Obierika values tradition, he also knows that Okonkwo’s role in Ikemefuna’s death was unnecessary.

Obierika gives insight into many events in the novel. He discusses the changes the white missionaries bring and the Igbo traditions of of gift-giving and mysticism. For instance, part of Chinua Achebe’s Things Fall Apart is devoted to the cultural tradition of marriage. Obierika’s daughter is married off, and he negotiates a bride price and his daughter’s uri, a type of marital celebration. Obierika invites Okonkwo to attend these important celebrations, highlighting their friendship and Obierika’s respect for Okonkwo.

While Okonkwo is exiled, Obierika helps the other clansmen burn down Okonkwo’s hut and farm, as is tradition following a banishment. Obierika visits Okonkwo in Mbanta, informs Okonkwo of news from Umuofia, and grows some of Okonkwo’s yams for him in Iguedo to sell to sharecroppers. Obierika brings these profits to Okonkwo when he visits Mbanta. During Okonkwo’s banishment, Obierika tells him the rumors about the white men and missionaries coming to the villages. The next time Obierika visits, he tells Okonkwo that the missionaries have taken over Iguedo. He tells Okonkwo that Nwoye has converted to the missionaries’ religion. Obierika’s observations during these tumultuous changes are level-headed. He serves as a balance to Okonkwo’s often violent decisions and Okonkwo’s wish to go to war with the white men.

Okonkwo, at the end of his seven-year banishment, asks Obierika to build new huts for him for his return, representing the trust between the two. Near the end of Things Fall Apart, Obierika is angry and confused about Okonkwo’s death. He berates the white men who come to help bury Okonkwo, saying that Okonkwo “was one of the greatest men in Umuofia. You drove him to kill himself; and now he will be buried like a dog.” Obierika can’t finish his sentence and his emotions take over. Obierika’s show of emotion illustrates the many changes that white men have brought. Here, the established “manliness” of not crying or showing grief is overturned.