Symbolism, Imagery, Allegory
Not to be totally morbid, but after reading a lot of books and seeing a lot of movies and TV shows, we know that writers have always come up with really creative ways for characters to kick the bucket. Drowning comes up more than once in Daniel Deronda. Now, George Eliot is a totally talented writer and definitely had the creative chops to come up with more than one way for characters to go. It seems like it could have been a very deliberate choice for her to bring up drowning not once but twice.
Just to recap, the first time we encounter drowning is when Daniel first meets Mirah. He's just rowing along one day when he sees Mirah soak her cloak in water to make it heavy and get ready to wrap herself in it and jump in the river. He intervenes, saving her life. Much later in the novel, Grandcourt and Gwendolen go out in a sailboat. Grandcourt is being a big jerk. The wind changes, and when Grandcourt tries to turn the sail it knocks him into the water. Gwendolen watches him drown.
We're not saying that there's any one definitive way to guess why Eliot brings up death by water twice – only she would know that and, uh, we can't ask her (isn't that always the problem?). Even so, the repetition of this image pushes us to become detectives and compare and contrast the two scenes. Think of metaphors and images as our clues. When we look at things from this perspective, we see a few different explanations bubble to the surface (sorry, we had to).
First of all, we think about the people who die (or, in Mirah's case, attempt to die). Take Mirah. She's good, sweet, and loving. She's just horribly depressed because she doesn't know where she belongs and she thinks she's lost her family. Grandcourt, on the other hand, is a huge – well, the words we want to use would require some bleeping out. He's not a good person. In stark contrast to Mirah, he's hurt every person in his wake, only thinking about himself, and he's not even a little remorseful. In fact, he's totally satisfied with himself. Isn't there some justice in the fact that Mirah is saved and Grandcourt isn't? The trope of death by water seems to show how the universe gets involved to save the good and punish the wicked. For a novel largely concerned with religion, it's only natural that some battle of good versus evil should go down at some point.
Let's also keep in mind that the scenes of death by water also shed light on the people who watch everything go down. Daniel involves himself immediately in saving a woman that he doesn't even know – he calls out to her, startling her. He tells her that there is hope for her life to be better. Gwendolen, on the other hand, doesn't just know the person she watches drown – she's married to him. It's only after she knows it's too late for Grandcourt that she realizes the consequences of her inaction and jumps in the water after him. We're not trying to say that Daniel is bad and Gwendolen is good, but their actions here carve out their roles out a little bit more. Daniel is the deliverer not just of Mirah, but supposedly of the future of the Jewish nation. Gwendolen is powerless before Grandcourt drowns. She tries to exercise power by choosing not to save him immediately and she feels powerless once more after she realizes he is dead.