Why is it relevant that Bernard is the first speaker in Section 4?

It is relevant that Bernard is the first speaker in Section 4 because it signifies that he has some power within the group. Prior to this, Bernard has begun every section as the speaker, showing the reader that he holds an important role within the group. However, each section up to this point has shown how the group is growing farther and farther apart, and this change in the structure parallels that development.