Why was there a rivalry between Baroka and Lakunle throughout the book?

Lakunle is a smart but arrogant twenty-three-year-old schoolteacher who lambasts Ilujinle for its backwards views. He wants the village to be modern, and he wants to wed Sidi and make her a modern wife (though he believes women are naturally inferior to men). He is reluctant to participate in the ways of the village but is usually drawn into them regardless. He despises Baroka and is jealous of him.

The wily and powerful Bale (i.e. leader) of the village, Baroka is always on the quest for more wives. He laments getting older and covets the young Sidi. He tricks Sidi and Sadiku, though, and ends up winning Sidi and avenging his shame after she initially refused to marry him.