What are the major differences between the first missionary who visits the tribe and the second one who replaces him?

In Umuofia, the Christians are led by a kindly white man named Mr. Brown. Mr. Brown restrains the zeal of some of the fanatical converts. A convert named Enoch is particularly violent, always stirring up trouble; Brown strives to moderate Enoch's excesses. Mr. Brown is a wise and patient man; he befriends many of the local great men, and earns their affection. He spends a good deal of time with Akunna; they speak through an interpreter on the subject of religion. Neither man converts the other, but Mr. Brown learns much about the local religion and concludes that missionary work should be subtle and indirect: direct confrontation will not work. He also tries hard to get people to send their children to the Christian school.

Mr. Brown's replacement is the Reverend James Smith, and he is not the tolerant and wise man that Mr. Brown was. Mr. Smith is fanatic and uncompromising, seeing the world entirely in terms of black and white. Under him, fanatics like Enoch flourish.