Mr. Murdstone is clearly the enemy of David's early days. Mr. Murdstone horns in on David's happy, peaceful relationship with his mother. He humiliates David until he feels stupid, lonely, and isolated from the world. He whips David and keeps him locked in a room for five days until he can send David to a vicious school, Salem House. And then, when David's mother dies, he sends David to a factory to work as a drudge with no money and no future. So yeah, we think it's fair to say that Mr. Murdstone is David's antagonist. But once Miss Betsey tells off Mr. Murdstone in Chapter 14, Mr. Murdstone's power over David is utterly broken. Miss Betsey is David's new guardian. So, we have to look to other characters to find new sources of conflict for our hero, David.