Jim’s wife quoted Martin Luther, the face of the Protestant Reformation in the early 16th century. The gist, as Jim sees it, is that it’s important and worthwhile to help, even if it ultimately won’t matter in the grand scheme of things. Then, when Jim says he and his wife wanted to save the ones they could, it’s an oblique reference to the fact that right now, Jim can’t save his daughter—but he can, perhaps, save the robber. When the robber asks for fireworks for Estelle, it highlights the strength of the bonds that the robber has formed with her hostages over the course of the hostage drama.